Last Modified: 05-13-2024 6.11:8.1.0 Doc ID: RM100000002B6E3
Model Year Start: 2023 Model: GR Corolla Prod Date Range: [03/2023 - 08/2023]
Title: NETWORKING: CAN COMMUNICATION SYSTEM (for Gasoline Model): DIAGNOSIS SYSTEM; 2023 MY Corolla Corolla Hatchback GR Corolla [03/2023 - 08/2023]

DIAGNOSIS SYSTEM

NOTICE:

The following communication bus check screen is provided only as an example. This screen differs from the actual screen for this vehicle.

Description of "Communication Bus Check" Screen

HINT:

The ECUs and sensors that are normally connected to the CAN communication system are displayed on the GTS.

(a) Select "Communication Bus Check" on the menu screen of the GTS.

CAN Bus Check

HINT:

If items are not selected correctly in the vehicle specification pop up screen, the name of the CAN junction connector to which the ECUs or sensors are connected may not be displayed on the "Communication Bus Check" screen.

(b) Confirm that the "Communication Bus Check" screen is displayed and the ECUs and sensors that have a history of being connected to the monitoring ECU are displayed.

HINT:

  • Even if an ECU or sensor that is connected to a bus that is monitored by a bus monitoring ECU (gateway function equipped ECU) is not communicating, it will remain displayed on the "Communication Bus Check" screen.
  • When an ECU or sensor that is connected to a bus that is not monitored by a bus monitoring ECU (gateway function equipped ECU) is not displayed on the "Communication Bus Check" screen, it means that it is not communicating.
  • ECUs with a history of being connected are displayed even if the ECUs are removed.

(c) The default display setting selected on the combo box is ALL. When checking for ECUs or sensors for a specific bus, choose the bus from the drop down list. ALL, each bus, each sub bus and Central Gateway are listed in the drop down list.

*a

Combo box

*b

Background color is red or yellow

Item

Detail

Combo box: ALL

Displays all ECUs and sensors connected to the central bus and sub buses.

Combo box: Bus

Displays ECUs and sensors connected to the selected bus.

Combo box: Sub bus

Displays ECUs and sensors connected to the selected sub bus.

Combo box: Central Gateway

Displays all ECUs and sensors connected to the central bus.

NOTICE:

  • When using the combo box, it may be possible to select a sub bus from the drop down list that does not have any connected ECUs or sensors. This is not a malfunction and occurs when there is no optional device connected to a sub bus which is monitored by a sub bus monitoring ECU (gateway function equipped ECU).
  • In the drop down list, all sub buses applicable to the model are displayed (e.g. LIN communication sub buses are also displayed). For information on sub buses necessary to diagnose the CAN communication system, refer to System Diagram.

    Click here 2023 MY Corolla Corolla Hatchback GR Corolla [03/2023 - 08/2023]; NETWORKING: CAN COMMUNICATION SYSTEM (for Gasoline Model): SYSTEM DIAGRAM

HINT:

The background color of an ECU or sensor changes according to its connection status as indicated in the following table.

Description of "Communication Bus Check" Screen

Bus Type

Background Color

Connection Status

Bus

White

Communication has been normal.

Yellow

Communication stop occurred at least once since the start of the CAN bus check, but communication is currently occurring (unstable communication).

Red

Currently not communicating (either of the following):

  • Not communicating since the start of the CAN bus check
  • Communication occurred at least once since the start of the CAN bus check, but is currently not occurring.

Not displayed

Either of the following:

  • The central gateway ECU (network gateway ECU) has an internal malfunction or cannot communicate with the GTS.*4
  • No ECUs or sensors are connected to the bus.*5

Sub bus with a gateway function equipped ECU that does not memorize connected ECUs or sensors*2

White

Communication has been normal since the start of the CAN bus check.

Yellow

Communication stop occurred at least once since the start of the CAN bus check, but communication is currently occurring (unstable communication).

Red

Communication occurred at least once since the start of the CAN bus check, but is currently not occurring.

Not displayed

Communication stop has continued since the start of the CAN bus check.*1

Sub bus with a gateway function equipped ECU that memorizes connected ECUs and sensors*3

White

Communication has been normal.

Yellow

Communication stop occurred at least once since the start of the CAN bus check, but communication is currently occurring (unstable communication).

Red

Currently not communicating (either of the following):

  • Not communicating since the start of the CAN bus check
  • Communication occurred at least once since the start of the CAN bus check, but is currently not occurring.

Not displayed

Either of the following:

  • The gateway function equipped ECU cannot communicate with the central gateway ECU.*6
  • No ECUs or sensors are connected to the sub bus.*7
  • Gateway function equipped ECUs relay signals between ECUs and sensors connected to different buses.
  • *1: An ECU or sensor is installed to the vehicle but is not displayed on the "Communication Bus Check" screen.
  • *2: The gateway function equipped ECU does not memorize ECUs and sensors connected to its respective sub bus.
  • *3: The gateway function equipped ECU memorizes ECUs and sensors connected to its respective sub bus.
  • *4: When the central gateway ECU (network gateway ECU) has an internal malfunction or cannot communicate with the GTS, the name of buses, sub buses, ECUs and sensors will not be displayed.
  • *5: When no ECUs or sensors are connected to a bus, the message "There is no system found on the communication Bus." will be displayed.
  • *6: When a gateway function equipped ECU cannot communicate with the central gateway ECU (network gateway ECU), the name of sub buses and ECUs or sensors connected to the sub bus will not be displayed.
  • *7: When no ECUs or sensors are connected to the sub bus, the message "There is no system found on the communication Bus." will be displayed.
  • If there is no communication between the GTS and the vehicle, or no ECUs or sensors are displayed as connected, check the central gateway ECU (network gateway ECU) and diagnosis bus (The bus that connects the DLC3 to the central gateway ECU (network gateway ECU)) for malfunctions.

(d) Monitor the screen for any ECU or sensor connection status changes for a period of 2 minutes.

HINT:

  • If an open occurs in one of the wires of a CAN branch line, it may interfere with the communication of other ECUs or sensors resulting in an incorrect state being displayed.
  • If the connection status changes intermittently during the inspection, repair the open in the branch line of the ECU or sensor that is not communicating, and then perform Communication Bus Check again.

NOTICE:

The following communication bus check screen is provided only as an example. This screen differs from the actual screen for this vehicle.

Description of "Communication Bus Check (Detail)" Screen

HINT:

The communication error history of ECUs or sensors which have communication error history can be displayed on the "Communication Bus Check (Detail)" screen.

(a) Select "Communication Bus Check" on the menu screen of the GTS.

CAN Bus Check

HINT:

If items are not selected correctly in the vehicle specification pop up screen, the name of the CAN junction connector to which the ECUs or sensors are connected may not be displayed on the "Communication Bus Check" screen.

(b) Select "Detail" on the "Communication Bus Check" screen.

*a

Communication Bus Check (Detail)

-

-

(c) Confirm that the "Communication Bus Check (Detail)" screen is displayed and the communication error history of the ECUs or sensors up to present is displayed.

HINT:

  • Lost Communication Time and Lost Communication Trip are only displayed for the central bus.
  • Lost Communication Time and Lost Communication Trip are not displayed for sub buses.

(d) The default display setting selected on the combo box is ALL. When checking for ECUs or sensors for a specific bus, choose the bus from the drop down list. ALL, each bus, each sub bus and Central Gateway are listed in the drop down list.

*a

Combo box

*b

Background color is red

Item

Detail

Combo box: ALL

Displays all ECUs and sensors connected to the central bus and sub buses.

Combo box: Bus

Displays ECUs and sensors connected to the selected bus.

Combo box: Sub bus

Displays ECUs and sensors connected to the selected sub bus.

Combo box: Central Gateway

Displays all ECUs and sensors connected to the central bus.

Bus Monitoring ECU

Displays the gateway function equipped ECU which monitors the selected bus or sub bus.

Current Trip

Displays the total number of trips up to now*

Lost Communication Time(s)

Displays the longest period of time in seconds that the ECU or sensor connected to the central bus was not communicating.

Lost Communication Trip

Displays the trip in which the longest period of time that the ECU or sensor connected to the central bus was not communicating occurred.

  • *: If the component has been replaced with a new one, the total number of trips after the replacement is displayed.

NOTICE:

  • The Lost Communication Time column displays the longest period of time in seconds that the central gateway ECU (network gateway ECU) detected a communication stop in the respective ECU or sensor.
  • The Lost Communication Trip column displays the trip in which the central gateway ECU (network gateway ECU) detected the longest communication stop in the respective ECU or sensor.
  • When using the combo box, it may be possible to select a sub bus from the drop down list that does not have any connected ECUs or sensors. This is not a malfunction and occurs when there is no optional device connected to a sub bus which is monitored by a sub bus monitoring ECU (gateway function equipped ECU).
  • In the drop down list, all sub buses applicable to the model are displayed (e.g. LIN communication sub buses are also displayed). For information on sub buses necessary to diagnose CAN communication system, refer to the System Diagram.

    Click here 2023 MY Corolla Corolla Hatchback GR Corolla [03/2023 - 08/2023]; NETWORKING: CAN COMMUNICATION SYSTEM (for Gasoline Model): SYSTEM DIAGRAM

HINT:

The background color of an ECU or sensor changes according to its connection status as indicated in the following table.

Description of "Communication Bus Check (Detail)" Screen

Bus Type

Background Color

Connection Status

Bus

White

Either of the following:

  • Communication has been normal.
  • Lost Communication Time is below 6 seconds.

Red

Lost Communication Time is 6 seconds or more.

Not displayed

Either of the following:

  • The central gateway ECU (network gateway ECU) has an internal malfunction or cannot communicate with the GTS.*1
  • No ECUs or sensors are connected to the bus.*2

Sub bus

White

Lost Communication Time is displayed as "-".

Not displayed

Either of the following:

  • The gateway function equipped ECU cannot communicate with the central gateway ECU.*3
  • No ECUs or sensors are connected to the sub bus.*4
  • If there is no communication between the GTS and the vehicle, or no ECUs or sensors are displayed as connected, check the central gateway ECU (network gateway ECU) and diagnosis bus (The bus that connects the DLC3 to the central gateway ECU (network gateway ECU)) for malfunctions.
  • Lost Communication Time and Lost Communication Trip are not displayed for sub buses.
  • *1: When the central gateway ECU (network gateway ECU) has an internal malfunction or cannot communicate with the GTS, the name of buses, sub buses, ECUs and sensors will not be displayed.
  • *2: When no ECUs or sensors are connected to a bus, the message "There is no system found on the communication Bus." will be displayed.
  • *3: When a gateway function equipped ECU cannot communicate with the central gateway ECU (network gateway ECU), the name of sub buses and ECUs or sensors connected to the sub bus will not be displayed.
  • *4: When no ECUs or sensors are connected to the sub bus, the message "There is no system found on the communication Bus." will be displayed.

Communication Bus Check (Communication Malfunction Check)

HINT:

DTCs related to CAN communication are displayed for each ECU on the GTS.

(a) Select "Communication Bus Check" on the menu screen of the GTS.

CAN Bus Check

(b) Select "Communication Malfunction Check" on the "Communication Bus Check" screen.

*a

Communication Malfunction Check

-

-

(c) Confirm that the "Communication Malfunction Check" screen is displayed and CAN communication DTCs for each ECU are displayed.

HINT:

When there are no CAN communication DTCs stored, no DTCs will be displayed.

How to Use "Communication Bus Check" Screen in Inspection

NOTICE:

The following CAN bus wiring diagram or communication bus check screen is provided only as an example. This wiring diagram or screen differs from the actual one for this vehicle.

HINT:

  • If the CAN communication system is currently malfunctioning, it is recommended to use Communication Bus Check rather than Communication DTCs for determining the suspected area.
  • Turn the ignition switch to ON, or perform the necessary operations to reproduce the problem symptom, select "Communication Bus Check" and wait approximately 2 minutes. Check the communication status of each ECU or sensor on the screen while performing this operation.

(a) If the CAN communication system is currently malfunctioning, determine the suspected area using Communication Bus Check as follows:

Problem Symptoms Table

Problem Symptom Pattern

Display on Communication Bus Check Screen

Suspected Area

A

Almost all of the ECUs and sensors connected to the malfunctioning CAN bus are displayed as not communicating on the "Communication Bus Check" screen.

  • Short between CAN bus lines (CANH and CANL)
  • Short to +B in a CAN bus line (CANH or CANL)
  • Short to ground in a CAN bus line (CANH or CANL)

B

ECUs or sensors farther from the central gateway ECU (network gateway ECU) than the open in the wires are displayed as not communicating on the "Communication Bus Check" screen.

Open in both wires of a main bus line in the central bus

C

One ECU or sensor is displayed as not communicating on the "Communication Bus Check" screen.

  • Open in both wires of a branch line connected to an ECU or sensor in the central bus
  • Internal malfunction of an ECU or sensor in the central bus
  • Malfunction in the power supplied to an ECU or sensor in the central bus

D

  • No ECUs or sensors are displayed on the "Communication Bus Check" screen.
  • All ECUs or sensors are displayed as not communicating on the "Communication Bus Check" screen.
  • Internal malfunction of the central gateway ECU (network gateway ECU)
  • Malfunction in the power supplied to the central gateway ECU (network gateway ECU)
  • Open in both wires of the branch line in the diagnosis bus (DLC3 - Central gateway ECU (network gateway ECU))
  • Short between CAN bus lines (CANH and CANL) in the diagnosis bus (DLC3 - Central gateway ECU (network gateway ECU))
  • Short to +B in a CAN bus line (CANH or CANL) in the diagnosis bus (DLC3 - Central gateway ECU (network gateway ECU))
  • Short to ground in a CAN bus line (CANH or CANL) in the diagnosis bus (DLC3 - Central gateway ECU (network gateway ECU))

E

One ECU or sensor is displayed as not communicating in multiple buses on the "Communication Bus Check" screen.

  • Internal malfunction of an ECU or sensor connected to multiple buses
  • Malfunction in the power supplied to an ECU or sensor connected to multiple buses

F

Some ECUs or sensors are displayed as not communicating in the central bus and other ECUs or sensors are displayed as not communicating in a sub bus.

  • Open in a wire of a branch line connected to an ECU or sensor in the central bus
  • Internal malfunction of an ECU or sensor in the central bus

G

A gateway function equipped ECU is displayed as not communicating in the central bus and ECUs and sensors connected to its respective sub bus are not displayed.

  • Open in both wires of a branch line connected to a gateway function equipped ECU
  • Internal malfunction of a gateway function equipped ECU
  • Malfunction in the power supplied to a gateway function equipped ECU

H

One ECU or sensor is displayed as not communicating in a sub bus on the "Communication Bus Check" screen.

  • Open in both wires of a branch line connected to an ECU or sensor in a sub bus
  • Internal malfunction of an ECU or sensor in a sub bus
  • Malfunction in the power supplied to an ECU or sensor in a sub bus

I

ECUs or sensors farther from the sub bus monitoring ECU (gateway function equipped ECU) than the open in the wires are displayed as not communicating on the "Communication Bus Check" screen.

Open in both wires of a main bus line in a sub bus

(b) Problem Symptom Pattern A

Display on Communication Bus Check Screen

Almost all of the ECUs and sensors connected to the malfunctioning CAN bus are displayed as not communicating on the "Communication Bus Check" screen.

Details of Malfunction

  • Short between CAN bus lines (CANH and CANL) in Bus 2
  • Short to +B in a CAN bus line (CANH or CANL) in Bus 2
  • Short to ground in a CAN bus line (CANH or CANL) in Bus 2

*a

Bus 2

*b

Bus 4

*c

Sub bus

*d

Diagnosis bus

*e

Location of malfunction

  • Short between CAN bus lines (CANH and CANL) in bus lines
  • Short to +B in a CAN bus line (CANH or CANL) in bus lines
  • Short to ground in a CAN bus line (CANH or CANL) in bus lines

*f

Background color is red

HINT:

  • Due to the malfunction, almost all of the ECUs and sensors connected to Bus 2 will be displayed as not communicating and their background color will be red.
  • The malfunction in Bus 2 will not affect the other buses.
  • The malfunctioning part can be determined by inspecting for an open in the main bus line, a short between bus lines or a short to +B or ground.
  • Make sure to perform the inspection to measure resistances of buses to determine the cause of the malfunction.

Display on Communication Bus Check Screen

Almost all of the ECUs and sensors connected to the malfunctioning CAN bus are displayed as not communicating on the "Communication Bus Check" screen.

Details of Malfunction

  • Short between CAN bus lines (CANH and CANL) in Bus 4
  • Short to +B in a CAN bus line (CANH or CANL) in Bus 4
  • Short to ground in a CAN bus line (CANH or CANL) in Bus 4

*a

Bus 2

*b

Bus 4

*c

Sub bus

*d

Diagnosis bus

*e

Location of malfunction

  • Short between CAN bus lines (CANH and CANL) in bus lines
  • Short to +B in a CAN bus line (CANH or CANL) in bus lines
  • Short to ground in a CAN bus line (CANH or CANL) in bus lines

*f

Background color is red

*g

Not displayed

-

-

HINT:

  • Due to the malfunction, almost all of the ECUs and sensors connected to Bus 4 will be displayed as not communicating and their background color will be red.
  • The malfunction will not affect the other buses of the central bus. However, the sub bus connected to Bus 4 is likely to be affected. The gateway function equipped ECU connected to Bus 4 will not communicate and consequently the sub bus and its respective ECUs or sensors monitored by the gateway function equipped ECU (sub bus monitoring ECU) will not be displayed, indicating that the gateway function equipped ECU is not communicating with the central gateway ECU (network gateway ECU).
  • The malfunctioning part can be determined by inspecting for an open in the main bus line, a short between bus lines or a short to +B or ground.
  • Make sure to perform the inspection to measure resistances of buses to determine the cause of the malfunction.

(c) Problem Symptom Pattern B

Display on Communication Bus Check Screen

ECUs or sensors farther from the central gateway ECU (network gateway ECU) than the open in the wires are displayed as not communicating on the "Communication Bus Check" screen.

Details of Malfunction

Open in both wires of the main bus line between CGW and No. 1 CAN junction connector in Bus 2

*a

Bus 2

*b

Bus 4

*c

Sub bus

*d

Diagnosis bus

*e

Location of malfunction (open in both wires of the main bus line)

*f

Background color is red

HINT:

  • Due to the malfunction, almost all of the ECUs and sensors connected to Bus 2 will be displayed as not communicating and their background color will be red.
  • The malfunction in Bus 2 will not affect the other buses.
  • The malfunctioning part can be determined by inspecting for an open in the main bus line.
  • Make sure to perform the inspection to measure resistances of buses to determine the cause of the malfunction.

Display on Communication Bus Check Screen

ECUs or sensors farther from the central gateway ECU (network gateway ECU) than the open in the wires are displayed as not communicating on the "Communication Bus Check" screen.

Details of Malfunction

Open in both wires of the main bus line between the No. 1 CAN junction connector and No. 2 CAN junction connector in Bus 2

*a

Bus 2

*b

Bus 4

*c

Sub bus

*d

Diagnosis bus

*e

Location of malfunction (open in both wires of the main bus line)

*f

Background color is red

HINT:

  • Due to the malfunction, ECUs or sensors farther from CGW than the open in the wires will be displayed as not communicating and their background color will be red.
  • The malfunction in Bus 2 will not affect the other buses.
  • The malfunctioning part can be determined by inspecting for an open in the main bus line.
  • Make sure to perform the inspection to measure resistances of buses to determine the cause of the malfunction.

Display on Communication Bus Check Screen

ECUs or sensors farther from the central gateway ECU (network gateway ECU) than the open in the wires are displayed as not communicating on the "Communication Bus Check" screen.

Details of Malfunction

Open in both wires of the main bus line between the No. 2 CAN junction connector and ENG in Bus 2

*a

Bus 2

*b

Bus 4

*c

Sub bus

*d

Diagnosis bus

*e

Location of malfunction (open in both wires of the main bus line)

*f

Background color is red

*g

Pattern 1

*h

Pattern 2

HINT:

  • Even when the same part of the main bus line is open, depending on internal electrical noise which changes according to the position of the open in the line, the information displayed on the "Communication Bus Check" screen may differ.
  • In pattern 2, the information displayed may be the same as when there is an open in both wires in the main bus line between the No. 1 CAN junction connector and No. 2 CAN junction connector, which may make it difficult to determine the malfunctioning part.
  • The malfunction in Bus 2 will not affect the other buses.
  • Make sure to perform the inspection to measure resistances of buses to determine the cause of the malfunction.

(d) Problem Symptom Pattern C

Display on Communication Bus Check Screen

One ECU or sensor is displayed as not communicating on the "Communication Bus Check" screen.

Details of Malfunction

  • Open in both wires of the branch line connected to F-MGC in Bus 2
  • Internal malfunction of F-MGC in Bus 2
  • Malfunction in the power supplied to F-MGC in Bus 2

*a

Bus 2

*b

Bus 4

*c

Sub bus

*d

Diagnosis bus

*e

Location of malfunction 1 (open in both wires of the branch line)

*f

Background color is red

*g

Location of malfunction 2

  • Internal malfunction
  • Power source malfunction

-

-

HINT:

The information displayed on the "Communication Bus Check" screen will be the same for an open in both wires of a branch line, an internal malfunction of an ECU or sensor or a malfunction in the power supplied to an ECU or sensor. In this example, the background color of the malfunctioning ECU or sensor will be red.

Display on Communication Bus Check Screen

One ECU or sensor is displayed as not communicating on the "Communication Bus Check" screen.

Details of Malfunction

Open in both wires of the branch line connected to ENG in Bus 4

*a

Bus 2

*b

Bus 4

*c

Sub bus

*d

Diagnosis bus

*e

Location of malfunction (open in both wires of the branch line)

*f

Background color is red

HINT:

  • The malfunction in Bus 4 will not affect the other buses.
  • Due to the malfunction, although ENG is communicating normally with CGW via Bus 2, it is not communicating with CGW via Bus 4. Consequently, it will be displayed as not communicating in Bus 4.

(e) Problem Symptom Pattern D

Display on Communication Bus Check Screen

  • No ECUs or sensors are displayed on the "Communication Bus Check" screen.
  • All ECUs or sensors are displayed as not communicating on the "Communication Bus Check" screen.

Details of Malfunction

  • Internal malfunction of CGW
  • Malfunction in the power supplied to CGW
  • Open in both wires of the branch lines in the diagnosis bus

*a

Bus 2

*b

Bus 4

*c

Sub bus

*d

Diagnosis bus

*e

Location of malfunction 1 (open in both wires of the branch line)

*f

Not displayed

*g

Location of malfunction 2 (Internal malfunction)

*h

Background color is red

*i

Pattern 1 (Malfunction occurred before CAN bus check)

*j

Pattern 2 (Malfunction occurred after CAN bus check)

HINT:

When there is no communication between the GTS and the vehicle, no ECUs or sensors will be displayed.

(f) Problem Symptom Pattern E

Display on Communication Bus Check Screen

One ECU or sensor is displayed as not communicating in multiple buses on the "Communication Bus Check" screen.

Details of Malfunction

  • Internal malfunction of BRK
  • Malfunction in the power supplied to BRK

*a

Bus 2

*b

Bus 4

*c

Sub bus

*d

Diagnosis bus

*e

Location of malfunction

  • Internal malfunction
  • Power source malfunction

*f

Background color is red

HINT:

The information displayed on the "Communication Bus Check" screen will be the same for an internal malfunction of an ECU or sensor, or a malfunction in the power supplied to an ECU or sensor.

Due to the malfunction, BRK is not communicating with CGW via both Bus 2 and Bus 4. Consequently, the background color of BRK will be red for both Bus 2 and Bus 4.

(g) Problem Symptom Pattern F

Display on Communication Bus Check Screen

Some ECUs or sensors are displayed as not communicating in the central bus and other ECUs or sensors are displayed as not communicating in a sub bus.

Details of Malfunction

  • Open in a wire of the branch line connected to HV in Bus 4
  • Internal malfunction of HV in Bus 4

*a

Bus 2

*b

Bus 4

*c

Sub bus

*d

Diagnosis bus

*e

Location of malfunction 1 (open in a wire of the branch line)

*f

Location of malfunction 2

  • Internal malfunction
  • Power source malfunction

*g

Background color is red

*h

Background color intermittently becomes yellow or red

*i

Not displayed or background color is yellow or red

-

-

HINT:

  • In the "Communication Bus Check" screen shown in the illustration, electrical noise in the CAN bus caused by an open in a wire in the branch line connected to HV interferes with the communication of MB causing unstable communication. Also, since MB is a gateway function equipped ECU, communication of ECUs connected to its respective sub bus will also be unstable.
  • In the "Communication Bus Check" screen shown in the illustration, because the background color of HV is red, it is suspected that HV is the most likely cause of the malfunction. Therefore, it is suspected that HV is not communicating.

(h) Problem Symptom Pattern G

Display on Communication Bus Check Screen

A gateway function equipped ECU is displayed as not communicating in the central bus and ECUs and sensors connected to its respective sub bus are not displayed.

Details of Malfunction

  • Open in both wires of the branch line connected to MB in Bus 4
  • Internal malfunction of MB in Bus 4
  • Malfunction in the power supplied to MB in Bus 4

*a

Bus 2

*b

Bus 4

*c

Sub bus

*d

Diagnosis bus

*e

Location of malfunction 1 (open in both wires of the branch line)

*f

Location of malfunction 2

  • Internal malfunction
  • Power source malfunction

*g

Background color is red

*h

Not displayed

HINT:

  • If there is a communication malfunction in a gateway function equipped ECU, ECUs connected to its respective sub bus will also be affected and will not be displayed.
  • In the "Communication Bus Check" screen shown in the illustration, MB is a gateway function equipped ECU. Therefore, MB is suspected as not communicating.

(i) Problem Symptoms Pattern H

Display on Communication Bus Check Screen

One ECU or sensor is displayed as not communicating in a sub bus on the "Communication Bus Check" screen.

Details of Malfunction

  • Internal malfunction of MIR-L in the sub bus
  • Malfunction in the power supplied to MIR-L in the sub bus
  • Open in both wires of the branch line connected to MIR-L in the sub bus

*a

Bus 2

*b

Bus 4

*c

Sub bus

*d

Diagnosis bus

*e

Location of malfunction 1 (open in both wires of the branch line)

*f

Location of malfunction 2

  • Internal malfunction
  • Power source malfunction

*g

Background color is red

-

-

HINT:

  • The malfunction in the sub bus will not affect the other buses.
  • When a gateway function equipped ECU memorizes ECUs and sensors connected to its respective sub bus and there is a communication malfunction in one of the ECUs or sensors, the background color of the ECU or sensor will change to red and the ECU or sensor will remain displayed.
  • The information displayed on the "Communication Bus Check" screen will be the same for an open in both wires of a branch line, an internal malfunction of an ECU or sensor or a malfunction in the power supplied to an ECU or sensor.

(j) Problem Symptom Pattern I

Display on Communication Bus Check Screen

ECUs or sensors farther from the sub bus monitoring ECU (gateway function equipped ECU) than the open in the wires are displayed as not communicating on the "Communication Bus Check" screen.

Details of Malfunction

Open in both wires of the main bus line in the sub bus

*a

Bus 2

*b

Bus 4

*c

Sub bus

*d

Diagnosis bus

*e

Location of malfunction (open in both wires of the main bus line)

*f

Background color is red

HINT:

Due to the malfunction, ECUs or sensors farther from the sub bus monitoring ECU (gateway function equipped ECU) than the open in the wires will be displayed as not communicating and their background color will be red.

How to Use "Communication Bus Check (Detail)" Screen in Inspection

(a) Even if the malfunction cannot be determined on the "Communication Bus Check" screen, determine the malfunctioning part using Communication Bus Check (Detail) as follows:

NOTICE:

  • The following CAN bus wiring diagram or communication bus check screen is provided only as an example. This wiring diagram or screen differs from the actual one for this vehicle.
  • The Lost Communication Time column displays the longest period of time in seconds that the central gateway ECU (network gateway ECU) detected a communication stop in the respective ECU or sensor.
  • The Lost Communication Trip column displays the trip in which the central gateway ECU (network gateway ECU) detected the longest communication stop in the respective ECU or sensor.
  • When using the combo box, it may be possible to select a sub bus from the drop down list that does not have any connected ECUs or sensors. This is not a malfunction and occurs when there is no optional device connected to a sub bus which is monitored by a sub bus monitoring ECU (gateway function equipped ECU).
  • In the drop down list, all sub buses applicable to the model are displayed (e.g. LIN communication sub buses are also displayed). For information on sub buses necessary to diagnose CAN communication system, refer to the System Diagram.

    Click here 2023 MY Corolla Corolla Hatchback GR Corolla [03/2023 - 08/2023]; NETWORKING: CAN COMMUNICATION SYSTEM (for Gasoline Model): SYSTEM DIAGRAM

HINT:

  • If the CAN communication system is currently malfunctioning, it is recommended to use Communication Bus Check rather than Communication Bus Check (Detail) for determining the suspected area.
  • The communication error history of ECUs or sensors which have communication error history can be displayed on the "Communication Bus Check (Detail)" screen.
  • Lost Communication Time and Lost Communication Trip are only displayed for the central bus.
  • Lost Communication Time and Lost Communication Trip are not displayed for sub buses.

(b) If there is an ECU or sensor displayed with a red background on the "Communication Bus Check (Detail)" screen to indicate that it was not communicating, it is suspected that the ECU or sensor was not communicating.

Details of Malfunction

Past malfunction in the wire harness or power supplied to F-MGC in Bus 2

*a

Bus 2

*b

Bus 4

*c

Sub bus

*d

Diagnosis bus

*e

Location of malfunction

  • Internal malfunction
  • Power source malfunction

*f

Background color is red

Description of "Communication Bus Check (Detail)" Screen

Bus Type

Background Color

Connection Status

Bus

White

Either of the following:

  • Communication has been normal.
  • Lost Communication Time is below 6 seconds.

Red

Lost Communication Time is 6 seconds or more.

Not displayed

Either of the following:

  • The central gateway ECU (network gateway ECU) has an internal malfunction or cannot communicate with the GTS.*1
  • No ECUs or sensors are connected to the bus.*2

Sub bus

White

Lost Communication Time is displayed as "-".

Not displayed

Either of the following:

  • The gateway function equipped ECU cannot communicate with the central gateway ECU.*3
  • No ECUs or sensors are connected to the sub bus.*4

HINT:

  • Check the values of Lost Communication Trip and Current Trip for the ECUs or sensors that have a red background color.
  • If the values of Lost Communication Trip and Current Trip are the same for an ECU or sensor, the ECU or sensor is currently not communicating. In this case, it is recommended to use Communication Bus Check rather than Communication Bus Check (Detail) for determining the suspected area.
  • In the "Communication Bus Check (Detail)" screen shown in the illustration, F-MGC had a communication malfunction in the 10th trip. Thus, it is suspected that F-MGC was not communicating.
  • *1: When the central gateway ECU (network gateway ECU) has an internal malfunction or cannot communicate with the GTS, the name of buses, sub buses, ECUs and sensors will not be displayed.
  • *2: When no ECUs or sensors are connected to a bus, the message "There is no system found on the communication Bus." will be displayed.
  • *3: When a gateway function equipped ECU cannot communicate with the central gateway ECU (network gateway ECU), the name of sub buses and ECUs or sensors connected to the sub bus will not be displayed.
  • *4: When no ECUs or sensors are connected to the sub bus, the message "There is no system found on the communication Bus." will be displayed.

DTC TABLE BY ECU

HINT:

  • In the CAN communication system, the CAN communication DTCs of each ECU can be displayed using the GTS.
  • If CAN communication system DTCs are output, the malfunction cannot be determined only by the DTCs. Perform troubleshooting according to How to Proceed with Troubleshooting.

    Click here 2023 MY Corolla Corolla Hatchback GR Corolla [03/2023 - 08/2023]; NETWORKING: CAN COMMUNICATION SYSTEM (for Gasoline Model): SYSTEM DIAGRAM

  • If there is a malfunction currently, DTCs can be checked by performing steps in the DTC check procedure.

(a) ECM / GTS Display "Engine"

Powertrain > Engine > Trouble Codes

HINT:

  • This ECU uses the CAN communication system for DTC communication.
  • *: Refer to SFI System.

    for M20A-FKS

    Click here 2023 - 2025 MY Corolla Corolla Hatchback [03/2023 -        ]; M20A-FKS (ENGINE CONTROL): SFI SYSTEM: U010187; Lost Communication with TCM Missing Message

DTC

Detection Item

DTC Detection Condition

DTC Detection Pre-condition

DTC Check Procedure

Warning Displayed

DTC Storage Method

Indication in Meter

Multi-information Display

U010187*

Lost Communication with TCM Missing Message

Communication stops between the ECM and the TCM for approximately 2 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 1 second or more.
  • The power source voltage of the ECM is 10 V or more.

Turn the ignition switch to ON and wait for at least approximately 4 seconds.

MIL illuminates.

-

DTC is stored until it is cleared using the GTS.

U012987

Lost Communication with Brake System Control Module Missing Message

Communication stops between the ECM and the brake actuator assembly for approximately 5 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 2 seconds or more.
  • The power source voltage of the ECM is 10 V or more.

Turn the ignition switch to ON and wait for at least approximately 10 seconds.

-

-

DTC is stored until it is cleared using the GTS.

U015587

Lost Communication with Instrument Panel Cluster (IPC) Control Module Missing Message

Communication stops between the ECM and the combination meter assembly for approximately 5 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the ECM is 10 V or more.

Turn the ignition switch to ON and wait for at least approximately 10 seconds.

MIL illuminates.

-

DTC is stored until it is cleared using the GTS.

U115C87

Lost Communication with ECM/PCM "A" (ch5) Missing Message

Communication stops between the ECM and the brake actuator assembly for approximately 2 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the ECM is 10 V or more.

Turn the ignition switch to ON and wait for at least approximately 4 seconds.

-

-

DTC is stored until it is cleared using the GTS.

(b) TCM / GTS Display "Transmission" (for CVT(K120))

Powertrain > Transmission > Trouble Codes

HINT:

  • This ECU uses the CAN communication system for DTC communication.
  • *: Refer to K120 Continuously Variable Transaxle System.

    Click here 2023 - 2025 MY Corolla Corolla Hatchback [11/2022 -        ]; K120 / K121 (CVT): K120 CONTINUOUSLY VARIABLE TRANSAXLE SYSTEM: U010087; Lost Communication with ECM/PCM "A" Missing Message

DTC

Detection Item

DTC Detection Condition

DTC Detection Pre-condition

DTC Check Procedure

Warning Displayed

DTC Storage Method

Indication in Meter

Multi-information Display

U010087*

Lost Communication with ECM/PCM "A" Missing Message

Communication stops between the TCM and the ECM for approximately 2 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 1 second or more.
  • The power source voltage of the TCM is 10.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 4 seconds.

MIL illuminates.

-

DTC is stored until it is cleared using the GTS.

U012987

Lost Communication with Brake System Control Module Missing Message

Communication stops between the TCM and the brake actuator assembly for approximately 3 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 2 seconds or more.
  • The power source voltage of the TCM is 10.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 6 seconds.

-

-

DTC is stored until it is cleared using the GTS.

(c) Brake Actuator Assembly / GTS Display "Brake/EPB"

Chassis > Brake/EPB > Trouble Codes

HINT:

  • This ECU uses the CAN communication system for DTC communication.
  • *1: for CVT (K120)
  • *2: except CVT (K120)

DTC

Detection Item

DTC Detection Condition

DTC Detection Pre-condition

DTC Check Procedure

Warning Displayed

DTC Storage Method

Indication in Meter

Multi-information Display

U007488

Control Module Communication Bus "B" Off Bus Off

Bus off is judged.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the brake actuator assembly is 9.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 3 seconds.

  • Brake system warning light illuminates.
  • ABS warning light illuminates.
  • Slip indicator light illuminates.

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

U010087

Lost Communication with ECM/PCM "A" Missing Message

Communication stops between the brake actuator assembly and the ECM for approximately 2 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the brake actuator assembly is 9.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 5 seconds.

  • ABS warning light illuminates.
  • Slip indicator light illuminates.

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

U010187

Lost Communication with TCM Missing Message

  • Communication stops between the brake actuator assembly and the TCM for approximately 2 seconds or more.*1
  • Communication stops between the brake actuator assembly and the ECM for approximately 2 seconds or more.*2

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the brake actuator assembly is 9.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 5 seconds.

  • Slip indicator light illuminates.
  • Brake hold operated indicator light blinks.
  • Brake warning light / yellow (minor malfunction) illuminates.

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

U012500

Lost Communication with Multi-axis Acceleration Sensor Module "A" (2WD) Missing Message

Communication stops between the brake actuator assembly and the airbag sensor assembly for approximately 5 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the brake actuator assembly is 9.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 8 seconds.

  • Brake system warning light illuminates.
  • ABS warning light illuminates.
  • Slip indicator light illuminates.

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

U012587

Lost Communication with Multi-axis Acceleration Sensor Module Missing Message

Communication stops between the brake actuator assembly and the airbag sensor assembly for approximately 5 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the brake actuator assembly is 9.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 8 seconds.

  • Brake system warning light illuminates.
  • ABS warning light illuminates.
  • Slip indicator light illuminates.

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

U012687

Lost Communication with Steering Angle Sensor Module Missing Message

Communication stops between the brake actuator assembly and the steering sensor for approximately 1 second or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the brake actuator assembly is 9.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 4 seconds.

Slip indicator light illuminates.

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

U013187

Lost Communication with Power Steering Control Module Missing Message

Communication stops between the brake actuator assembly and the power steering ECU with motor assembly for approximately 1 second or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the brake actuator assembly is 9.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 4 seconds.

  • Slip indicator light illuminates.
  • Brake hold operated indicator light blinks.

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

U014087

Lost Communication with Body Control Module Missing Message

Communication stops between the brake actuator assembly and the main body ECU (multiplex network body ECU) for approximately 2 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the brake actuator assembly is 9.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 5 seconds.

  • Brake warning light / yellow (minor malfunction) illuminates.
  • Brake hold operated indicator light blinks.

-

DTC is stored until it is cleared using the GTS.

U015187

Lost Communication with Restraints Control Module Missing Message

Communication stops between the brake actuator assembly and the airbag sensor assembly for approximately 5 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the brake actuator assembly is 9.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 8 seconds.

-

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

U115C87

Lost Communication with ECM/PCM "A" (ch5) Missing Message

Communication stops between the brake actuator assembly and the ECM for approximately 2 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the brake actuator assembly is 9.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 5 seconds.

  • ABS warning light illuminates.
  • Slip indicator light illuminates.

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

(d) Power Steering ECU with Motor Assembly / GTS Display "EMPS"

Chassis > EMPS > Trouble Codes

HINT:

This ECU uses the CAN communication system for DTC communication.

DTC

Detection Item

DTC Detection Condition

DTC Detection Pre-condition

DTC Check Procedure

Warning Displayed

DTC Storage Method

Indication in Meter

Multi-information Display

U010087

Lost Communication with ECM/PCM "A" Missing Message

Communication stops between the power steering ECU with motor assembly and the ECM for approximately 300 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • Vehicle speed is 20 km/h (12 mph) or more.
  • The power source voltage of the power steering ECU with motor assembly is 9 V or more.

Drive the vehicle at a speed of 20 km/h (12 mph) or more for approximately 300 seconds or more.

-

-

DTC remains stored only while malfunction is occurring.

U012687

Lost Communication with Steering Angle Sensor Module Missing Message

Communication stops between the power steering ECU with motor assembly and the steering sensor for approximately 3 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the power steering ECU with motor assembly is 9 V or more.

Turn the ignition switch to ON and wait for at least approximately 6 seconds.

EPS warning light illuminates.

-

DTC remains stored only while malfunction is occurring.

U012987

Lost Communication With Brake System Control Module Missing Message

Communication stops between the power steering ECU with motor assembly and the brake actuator assembly for approximately 3 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the power steering ECU with motor assembly is 9 V or more.

Turn the ignition switch to ON and wait for at least approximately 6 seconds.

EPS warning light illuminates.

-

DTC remains stored only while malfunction is occurring.

U023A87

Lost Communication with Image Processing Module "A" Missing Message

Communication stops between the power steering ECU with motor assembly and the forward recognition camera for approximately 3 seconds or more.

The ignition switch is ON for approximately 3 seconds or more.

Turn the ignition switch to ON and wait for at least approximately 5 seconds.

-

-

DTC remains stored only while malfunction is occurring.

(e) Main Body ECU (Multiplex Network Body ECU) / GTS Display "Main Body"

Body Electrical > Main Body > Trouble Codes

HINT:

This ECU uses the CAN communication system for DTC communication.

DTC

Detection Item

DTC Detection Condition

DTC Detection Pre-condition

DTC Check Procedure

Warning Displayed

DTC Storage Method

Indication in Meter

Multi-information Display

U010087

Lost Communication with ECM/PCM "A" Missing Message

Communication stops between the main body ECU (multiplex network body ECU) and the ECM for approximately 10 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 10 seconds or more.
  • The power source voltage of the main body ECU (multiplex network body ECU) is 10 V or more.

Turn the ignition switch to ON and wait for at least approximately 20 seconds.

-

-

DTC is stored until it is cleared using the GTS.

U010187

Lost Communication with TCM Missing Message

  • Communication stops between the main body ECU (multiplex network body ECU) and the ECM for approximately 10 seconds or more.
  • Communication stops between the main body ECU (multiplex network body ECU) and the TCM for approximately 10 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 10 seconds or more.
  • The power source voltage of the main body ECU (multiplex network body ECU) is 10 V or more.

Turn the ignition switch to ON and wait for at least approximately 20 seconds.

-

-

DTC is stored until it is cleared using the GTS.

U012687

Lost Communication with Steering Angle Sensor Module Missing Message

Communication stops between the main body ECU (multiplex network body ECU) and the steering sensor for approximately 10 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 10 seconds or more.
  • The power source voltage of the main body ECU (multiplex network body ECU) is 10 V or more.

Turn the ignition switch to ON and wait for at least approximately 20 seconds.

-

-

DTC is stored until it is cleared using the GTS.

U012987

Lost Communication with Brake System Control Module "A" Missing Message

Communication stops between the main body ECU (multiplex network body ECU) and the brake actuator assembly for approximately 10 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 10 seconds or more.
  • The power source voltage of the main body ECU (multiplex network body ECU) is 10 V or more.

Turn the ignition switch to ON and wait for at least approximately 20 seconds.

-

-

DTC is stored until it is cleared using the GTS.

U015187

Lost Communication with Restraints Control Module Missing Message

Communication stops between the main body ECU (multiplex network body ECU) and the airbag sensor assembly for approximately 10 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 10 seconds or more.
  • The power source voltage of the main body ECU (multiplex network body ECU) is 10 V or more.

Turn the ignition switch to ON and wait for at least approximately 20 seconds.

-

-

DTC is stored until it is cleared using the GTS.

U015587

Lost Communication with Instrument Panel Cluster (IPC) Control Module Missing Message

Communication stops between the main body ECU (multiplex network body ECU) and the combination meter assembly for approximately 10 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 10 seconds or more.
  • The power source voltage of the main body ECU (multiplex network body ECU) is 10 V or more.

Turn the ignition switch to ON and wait for at least approximately 20 seconds.

-

-

DTC is stored until it is cleared using the GTS.

U016387

Lost Communication with Navigation Control Module Missing Message

Communication stops between the main body ECU (multiplex network body ECU) and the radio and display receiver assembly for approximately 10 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 10 seconds or more.
  • The power source voltage of the main body ECU (multiplex network body ECU) is 10 V or more.

Turn the ignition switch to ON and wait for at least approximately 20 seconds.

-

-

DTC is stored until it is cleared using the GTS.

U016487

Lost Communication with HVAC Control Module Missing Message

Communication stops between the main body ECU (multiplex network body ECU) and the air conditioning amplifier assembly for approximately 10 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 10 seconds or more.
  • The power source voltage of the main body ECU (multiplex network body ECU) is 10 V or more.

Turn the ignition switch to ON and wait for at least approximately 20 seconds.

-

-

DTC is stored until it is cleared using the GTS.

U016887

Lost Communication with Vehicle Security Control Module Missing Message

Communication stops between the main body ECU (multiplex network body ECU) and the certification ECU (smart key ECU assembly) for approximately 10 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 10 seconds or more.
  • The power source voltage of the main body ECU (multiplex network body ECU) is 10 V or more.

Turn the ignition switch to ON and wait for at least approximately 20 seconds.

-

-

DTC is stored until it is cleared using the GTS.

U023A87

Lost Communication with Image Processing Module "A" Missing Message

Communication stops between the main body ECU (multiplex network body ECU) and the forward recognition camera for approximately 10 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 10 seconds or more.
  • The power source voltage of the main body ECU (multiplex network body ECU) is 10 V or more.

Turn the ignition switch to ON and wait for at least approximately 20 seconds.

-

-

DTC is stored until it is cleared using the GTS.

U110687

Lost Communication with Electric Parking Brake Module Missing Message

Communication stops between the main body ECU (multiplex network body ECU) and the brake actuator assembly for approximately 10 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 10 seconds or more.
  • The power source voltage of the main body ECU (multiplex network body ECU) is 10 V or more.

Turn the ignition switch to ON and wait for at least approximately 20 seconds.

-

-

DTC is stored until it is cleared using the GTS.

U110787

Lost Communication with Power Management Module Missing Message

Communication stops between the main body ECU (multiplex network body ECU) and the certification ECU (smart key ECU assembly) for approximately 10 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 10 seconds or more.
  • The power source voltage of the main body ECU (multiplex network body ECU) is 10 V or more.

Turn the ignition switch to ON and wait for at least approximately 20 seconds.

-

-

DTC is stored until it is cleared using the GTS.

U111787

Lost Communication with Accessory Gateway Missing Message

Communication stops between the main body ECU (multiplex network body ECU) and the option connector (bus buffer ECU) for approximately 10 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 10 seconds or more.
  • The power source voltage of the main body ECU (multiplex network body ECU) is 10 V or more.

Turn the ignition switch to ON and wait for at least approximately 20 seconds.

-

-

DTC is stored until it is cleared using the GTS.

(f) Combination Meter Assembly / GTS Display "Combination Meter"

Body Electrical > Combination Meter > Trouble Codes

HINT:

This ECU uses the CAN communication system for DTC communication.

DTC

Detection Item

DTC Detection Condition

DTC Detection Pre-condition

DTC Check Procedure

Warning Displayed

DTC Storage Method

Indication in Meter

Multi-information Display

U010087

Lost Communication with ECM/PCM "A" Missing Message

Communication stops between the combination meter assembly and the ECM for approximately 4 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the combination meter assembly is 10.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 7 seconds.

MIL illuminates.

-

DTC is stored until it is cleared using the GTS.

U011487

Lost Communication with Four-Wheel Drive Clutch Control Module Missing Message

Communication stops between the combination meter assembly and the 4WD ECU assembly for approximately 5 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the combination meter assembly is 10.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 8 seconds.

-

-

DTC is stored until it is cleared using the GTS.

U012687

Lost Communication with Steering Angle Sensor Module Missing Message

Communication stops between the combination meter assembly and the steering sensor for approximately 5 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the combination meter assembly is 10.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 8 seconds.

-

-

DTC is stored until it is cleared using the GTS.

U012787

Lost Communication with Tire Pressure Monitor Module Missing Message

Communication stops between the combination meter assembly and the tire pressure warning ECU and receiver for approximately 5 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the combination meter assembly is 10.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 8 seconds.

-

-

DTC is stored until it is cleared using the GTS.

U012987

Lost Communication with Brake System Control Module Missing Message

Communication stops between the combination meter assembly and the brake actuator assembly for approximately 4 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the combination meter assembly is 10.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 7 seconds.

  • ABS warning light illuminates.
  • Brake system warning light illuminates.

-

DTC is stored until it is cleared using the GTS.

U013187

Lost Communication with Power Steering Control Module Missing Message

Communication stops between the combination meter assembly and the power steering ECU with motor assembly for approximately 4 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the combination meter assembly is 10.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 7 seconds.

EPS warning light illuminates.

-

DTC is stored until it is cleared using the GTS.

U013287

Lost Communication with Suspension Control Module "A" Missing Message

Communication stops between the combination meter assembly and the absorber control ECU for approximately 10 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the combination meter assembly is 10.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 13 seconds.

-

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

U014087

Lost Communication with Body Control Module Missing Message

Communication stops between the combination meter assembly and the main body ECU (multiplex network body ECU) for approximately 5 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the combination meter assembly is 10.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 8 seconds.

-

-

DTC is stored until it is cleared using the GTS.

U015187

Lost Communication with Restraints Control Module Missing Message

Communication stops between the combination meter assembly and the airbag sensor assembly for approximately 5 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the combination meter assembly is 10.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 8 seconds.

SRS warning light illuminates.

-

DTC is stored until it is cleared using the GTS.

U016387

Lost Communication with Navigation Control Module Missing Message

Communication stops between the combination meter assembly and the radio and display receiver assembly for approximately 5 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the combination meter assembly is 10.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 8 seconds.

-

-

DTC is stored until it is cleared using the GTS.

U016487

Lost Communication with HVAC Control Module Missing Message

Communication stops between the combination meter assembly and the air conditioning amplifier assembly for approximately 5 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the combination meter assembly is 10.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 8 seconds.

-

-

DTC is stored until it is cleared using the GTS.

U016887

Lost Communication with Vehicle Security Control Module Missing Message

Communication stops between the combination meter assembly and the certification ECU (smart key ECU assembly) for approximately 5 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the combination meter assembly is 10.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 8 seconds.

-

-

DTC is stored until it is cleared using the GTS.

U023387

Lost Communication with Side Obstacle Detection Control Module "B" Missing Message

Communication stops between the combination meter assembly and the blind spot monitor sensor LH (B) for approximately 5 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the combination meter assembly is 10.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 8 seconds.

-

-

DTC is stored until it is cleared using the GTS.

U023A87

Lost Communication with Image Processing Module "A" Missing Message

Communication stops between the combination meter assembly and the forward recognition camera for approximately 5 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the combination meter assembly is 10.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 8 seconds.

-

-

DTC is stored until it is cleared using the GTS.

U111287

Lost Communication with Combination Switch Module Missing Message

Communication stops between the combination meter assembly and the steering sensor for approximately 10 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the combination meter assembly is 10.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 13 seconds.

-

-

DTC is stored until it is cleared using the GTS.

U111787

Lost Communication with Accessory Gateway Missing Message

Communication stops between the combination meter assembly and the option connector (bus buffer ECU) for approximately 5 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the combination meter assembly is 10.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 8 seconds.

-

-

DTC is stored until it is cleared using the GTS.

U113387

Lost Communication with PMN Module Missing Message

Communication stops between the combination meter assembly and the certification ECU (smart key ECU assembly) for approximately 4 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the combination meter assembly is 10.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 7 seconds.

-

-

DTC is stored until it is cleared using the GTS.

(g) Certification ECU (Smart Key ECU Assembly) / GTS Display "Entry&Start"

Body Electrical > Entry&Start > Trouble Codes

HINT:

This ECU uses the CAN communication system for DTC communication.

DTC

Detection Item

DTC Detection Condition

DTC Detection Pre-condition

DTC Check Procedure

Warning Displayed

DTC Storage Method

Indication in Meter

Multi-information Display

U010087

Lost Communication with ECM/PCM "A" Missing Message

Communication stops between the certification ECU (smart key ECU assembly) and the ECM for approximately 10 seconds or more.

All conditions are met:

  • Power source status change (+B OFF → ON, ACC ON ←→ OFF, IG ON ←→ OFF) is detected and approximately 10 seconds or more elapse.
  • The power source voltage of the certification ECU (smart key ECU assembly) is 10 V or more.

Turn the ignition switch to ON and wait for at least approximately 20 seconds.

-

-

DTC is stored until it is cleared using the GTS.

U012987

Lost Communication with Brake System Control Module "A" Missing Message

Communication stops between the certification ECU (smart key ECU assembly) and the brake actuator assembly for approximately 10 seconds or more.

All conditions are met:

  • Power source status change (+B OFF → ON, ACC ON ←→ OFF, IG ON ←→ OFF) is detected and approximately 10 seconds or more elapse.
  • The power source voltage of the certification ECU (smart key ECU assembly) is 10 V or more.

Turn the ignition switch to ON and wait for at least approximately 20 seconds.

-

-

DTC is stored until it is cleared using the GTS.

U014087

Lost Communication with Body Control Module Missing Message

Communication stops between the certification ECU (smart key ECU assembly) and the main body ECU (multiplex network body ECU) for approximately 10 seconds or more.

All conditions are met:

  • Power source status change (+B OFF → ON, ACC ON ←→ OFF, IG ON ←→ OFF) is detected and approximately 10 seconds or more elapse.
  • The power source voltage of the certification ECU (smart key ECU assembly) is 10 V or more.

Turn the ignition switch to ON and wait for at least approximately 20 seconds.

-

-

DTC is stored until it is cleared using the GTS.

U015587

Lost Communication with Instrument Panel Cluster (IPC) Control Module Missing Message

Communication stops between the certification ECU (smart key ECU assembly) and the combination meter assembly for approximately 10 seconds or more.

All conditions are met:

  • Power source status change (+B OFF → ON, ACC ON ←→ OFF, IG ON ←→ OFF) is detected and approximately 10 seconds or more elapse.
  • The power source voltage of the certification ECU (smart key ECU assembly) is 10 V or more.

Turn the ignition switch to ON and wait for at least approximately 20 seconds.

-

-

DTC is stored until it is cleared using the GTS.

U016487

Lost Communication with HVAC Control Module Missing Message

Communication stops between the certification ECU (smart key ECU assembly) and the air conditioning amplifier assembly for approximately 10 seconds or more.

All conditions are met:

  • Power source status change (+B OFF → ON, ACC ON ←→ OFF, IG ON ←→ OFF) is detected and approximately 10 seconds or more elapse.
  • The power source voltage of the certification ECU (smart key ECU assembly) is 10 V or more.

Turn the ignition switch to ON and wait for at least approximately 20 seconds.

-

-

DTC is stored until it is cleared using the GTS.

U111787

Lost Communication with Accessory Gateway Missing Message

Communication stops between the certification ECU (smart key ECU assembly) and the option connector (bus buffer ECU) for approximately 10 seconds or more.

All conditions are met:

  • Power source status change (+B OFF → ON, ACC ON ←→ OFF, IG ON ←→ OFF) is detected and approximately 10 seconds or more elapse.
  • The power source voltage of the certification ECU (smart key ECU assembly) is 10 V or more.

Turn the ignition switch to ON and wait for at least approximately 20 seconds.

-

-

DTC is stored until it is cleared using the GTS.

(h) Certification ECU (Smart Key ECU Assembly) / GTS Display "Power Source Control"

Body Electrical > Power Source Control > Trouble Codes

HINT:

This ECU uses the CAN communication system for DTC communication.

DTC

Detection Item

DTC Detection Condition

DTC Detection Pre-condition

DTC Check Procedure

Warning Displayed

DTC Storage Method

Indication in Meter

Multi-information Display

U010087

Lost Communication with ECM/PCM "A" Missing Message

Communication stops between the certification ECU (smart key ECU assembly) and the ECM for approximately 4 seconds or more.

All conditions are met:

  • The ignition switch is ON.
  • The power source voltage of the certification ECU (smart key ECU assembly) is 10 V or more.

Turn the ignition switch to ON and wait for at least approximately 4 seconds.

-

-

DTC is stored until it is cleared using the GTS.

U012987

Lost Communication with Brake System Control Module "A" Missing Message

Communication stops between the certification ECU (smart key ECU assembly) and the brake actuator assembly for approximately 4 seconds or more.

All conditions are met:

  • The ignition switch is ON.
  • The power source voltage of the certification ECU (smart key ECU assembly) is 10 V or more.

Turn the ignition switch to ON and wait for at least approximately 4 seconds.

-

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

U014087

Lost Communication with Body Control Module Missing Message

Communication stops between the certification ECU (smart key ECU assembly) and the main body ECU (multiplex network body ECU) for approximately 3 seconds or more.

All conditions are met:

  • The ignition switch is ON.
  • The power source voltage of the certification ECU (smart key ECU assembly) is 10 V or more.

Turn the ignition switch to ON and wait for at least approximately 3 seconds.

-

-

DTC is stored until it is cleared using the GTS.

U015587

Lost Communication with Instrument Panel Cluster (IPC) Control Module Missing Message

Communication stops between the certification ECU (smart key ECU assembly) and the combination meter assembly for approximately 5 seconds or more.

All conditions are met:

  • The ignition switch is ON.
  • The power source voltage of the certification ECU (smart key ECU assembly) is 10 V or more.

Turn the ignition switch to ON and wait for at least approximately 5 seconds.

-

-

DTC is stored until it is cleared using the GTS.

U111787

Lost Communication with Accessory Gateway Missing Message

Communication stops between the certification ECU (smart key ECU assembly) and the option connector (bus buffer ECU) for approximately 5 seconds or more.

All conditions are met:

  • The ignition switch is ON.
  • The power source voltage of the certification ECU (smart key ECU assembly) is 10 V or more.

Turn the ignition switch to ON and wait for at least approximately 5 seconds.

-

-

DTC is stored until it is cleared using the GTS.

(i) Air Conditioning Amplifier Assembly / GTS Display "Air Conditioner"

Body Electrical > Air Conditioner > Trouble Codes

HINT:

This ECU uses the CAN communication system for DTC communication.

DTC

Detection Item

DTC Detection Condition

DTC Detection Pre-condition

DTC Check Procedure

Warning Displayed

DTC Storage Method

Indication in Meter

Multi-information Display

U010087

Lost Communication with ECM/PCM "A" Missing Message

Communication stops between the air conditioning amplifier assembly and the ECM for approximately 10 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 10 seconds or more.
  • The power source voltage of the air conditioning amplifier assembly is 10 V or more.

Turn the ignition switch to ON and wait for at least approximately 20 seconds.

-

-

DTC is stored until it is cleared using the GTS.

U013187

Lost Communication with Power Steering Control Module Missing Message

Communication stops between the air conditioning amplifier assembly and the power steering ECU with motor assembly for approximately 10 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 10 seconds or more.
  • The power source voltage of the air conditioning amplifier assembly is 10 V or more.

Turn the ignition switch to ON and wait for at least approximately 20 seconds.

-

-

DTC is stored until it is cleared using the GTS.

U014087

Lost Communication with Body Control Module Missing Message

Communication stops between the air conditioning amplifier assembly and the main body ECU (multiplex network body ECU) for approximately 10 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 10 seconds or more.
  • The power source voltage of the air conditioning amplifier assembly is 10 V or more.

Turn the ignition switch to ON and wait for at least approximately 20 seconds.

-

-

DTC is stored until it is cleared using the GTS.

U015587

Lost Communication with Instrument Panel Cluster (IPC) Control Module Missing Message

Communication stops between the air conditioning amplifier assembly and the combination meter assembly for approximately 10 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 10 seconds or more.
  • The power source voltage of the air conditioning amplifier assembly is 10 V or more.

Turn the ignition switch to ON and wait for at least approximately 20 seconds.

-

-

DTC is stored until it is cleared using the GTS.

U016387

Lost Communication with Navigation Control Module Missing Message

Communication stops between the air conditioning amplifier assembly and the radio and display receiver assembly for approximately 10 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 10 seconds or more.
  • The power source voltage of the air conditioning amplifier assembly is 10 V or more.

Turn the ignition switch to ON and wait for at least approximately 20 seconds.

-

-

DTC is stored until it is cleared using the GTS.

U016887

Lost Communication with Vehicle Security Control Module Missing Message

Communication stops between the air conditioning amplifier assembly and the certification ECU (smart key ECU assembly) for approximately 10 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 10 seconds or more.
  • The power source voltage of the air conditioning amplifier assembly is 10 V or more.

Turn the ignition switch to ON and wait for at least approximately 20 seconds.

-

-

DTC is stored until it is cleared using the GTS.

(j) Millimeter Wave Radar Sensor Assembly / GTS Display "Front Radar Sensor"

Body Electrical > Front Radar Sensor > Trouble Codes

HINT:

  • This ECU uses the CAN communication system for DTC communication.
  • *: Refer to Front Radar Sensor System.

    Click here 2023 - 2025 MY Corolla Corolla Hatchback Corolla HV GR Corolla [11/2022 -        ]; ADVANCED DRIVER ASSISTANCE SYSTEM: FRONT RADAR SENSOR SYSTEM: DIAGNOSTIC TROUBLE CODE CHART

DTC

Detection Item

DTC Detection Condition

DTC Detection Pre-condition

DTC Check Procedure

Warning Displayed

DTC Storage Method

Indication in Meter

Multi-information Display

U010487*

Lost Communication with Cruise Control Module Missing Message

Communication stops between the forward recognition camera and the millimeter wave radar sensor assembly for approximately 1 second or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the millimeter wave radar sensor assembly is 9.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 4 seconds.

-

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

U130C51*

Software Incompatibility with Image Processing Module "A" Not Programmed

The vehicle information sent from the forward recognition camera remains undefined by the millimeter wave radar sensor assembly for approximately 7 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the millimeter wave radar sensor assembly is 9.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 10 seconds.

-

Displays messages on the multi-information display.

DTC remains stored only while malfunction is occurring.

U130C57*

Software Incompatibility with Image Processing Module "A" Invalid / Incompatible Software Component

The vehicle information sent from the forward recognition camera does not match that stored in the millimeter wave radar sensor assembly.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the millimeter wave radar sensor assembly is 9.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 3 seconds.

-

Displays messages on the multi-information display.

DTC remains stored only while malfunction is occurring.

(k) Forward Recognition Camera / GTS Display "Front Recognition Camera"

Chassis > Front Recognition Camera > Trouble Codes

HINT:

  • This ECU uses the CAN communication system for DTC communication.
  • *: Refer to Front Camera System.

    Click here 2023 MY Corolla Corolla Hatchback Corolla HV GR Corolla [11/2022 - 08/2023]; ADVANCED DRIVER ASSISTANCE SYSTEM: FRONT CAMERA SYSTEM: DIAGNOSTIC TROUBLE CODE CHART

DTC

Detection Item

DTC Detection Condition

DTC Detection Pre-condition

DTC Check Procedure

Warning Displayed

DTC Storage Method

Indication in Meter

Multi-information Display

U010087

Lost Communication with ECM/PCM "A" Missing Message

Communication stops between the forward recognition camera and the ECM for approximately 3 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the forward recognition camera is 9.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 6 seconds.

PCS warning light illuminates.

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

U010187

Lost Communication with TCM Missing Message

  • Communication stops between the forward recognition camera and the ECM for approximately 8 seconds or more.
  • Communication stops between the forward recognition camera and the TCM for approximately 8 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the forward recognition camera is 9.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 11 seconds.

PCS warning light illuminates.

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

U011487

Lost Communication with Four-Wheel Drive Clutch Control Module Missing Message

Communication stops between the forward recognition camera and the 4WD ECU assembly for approximately 3 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the forward recognition camera is 9.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 6 seconds.

PCS warning light illuminates.

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

U012687

Lost Communication with Steering Angle Sensor Module Missing Message

Communication stops between the forward recognition camera and the steering sensor for approximately 1 second or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the forward recognition camera is 9.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 4 seconds.

PCS warning light illuminates.

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

U012987

Lost Communication with Brake System Control Module "A" Missing Message

Communication stops between the forward recognition camera and the brake actuator assembly for approximately 2 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the forward recognition camera is 9.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 5 seconds.

PCS warning light illuminates.

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

U013187

Lost Communication with Power Steering Control Module "A" Missing Message

Communication stops between the forward recognition camera and the power steering ECU with motor assembly for approximately 1 second or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the forward recognition camera is 9.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 4 seconds.

PCS warning light illuminates.

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

U014087

Lost Communication with Body Control Module Missing Message

Communication stops between the forward recognition camera and the main body ECU (multiplex network body ECU) for approximately 8 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the forward recognition camera is 9.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 11 seconds.

-

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

U015187

Lost Communication with Restraints Control Module Missing Message

Communication stops between the forward recognition camera and the airbag sensor assembly for approximately 8 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the forward recognition camera is 9.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 11 seconds.

-

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

U015587

Lost Communication with Instrument Panel Cluster (IPC) Control Module Missing Message

Communication stops between the forward recognition camera and the combination meter assembly for approximately 8 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the forward recognition camera is 9.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 11 seconds.

-

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

U016387

Lost Communication with Navigation Control Module Missing Message

Communication stops between the forward recognition camera and the radio and display receiver assembly for approximately 5 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the forward recognition camera is 9.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 8 seconds.

-

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

U019887

Lost Communication with Telematic Control Module "A" Missing Message

Communication stops between the forward recognition camera and the DCM (telematics transceiver) for approximately 8 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the forward recognition camera is 9.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 11 seconds.

-

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

U023387

Lost Communication with Side Obstacle Detection Control Module "B" Missing Message

Communication stops between the forward recognition camera and the blind spot monitor sensor LH (B) for approximately 8 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the forward recognition camera is 9.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 11 seconds.

-

-

DTC is stored until it is cleared using the GTS.

U023587*

Lost Communication with Cruise Control Front Distance Range Sensor Single Sensor or Center Missing Message

Communication stops between the forward recognition camera and the millimeter wave radar sensor assembly for approximately 5 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the forward recognition camera is 9.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 8 seconds.

PCS warning light illuminates.

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

U030051*

Internal Control Module Software Incompatibility Not Programmed

When the forward recognition camera cannot confirm the Powertrain Information based on Powertrain Information sent from ECM

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the forward recognition camera is 9.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 3 seconds.

PCS warning light illuminates.

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

U030057*

Internal Control Module Software Incompatibility Invalid / Incompatible Software Component

When the Powertrain Information value sent from ECM does not match the value stored in the forward recognition camera

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the forward recognition camera is 9.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 3 seconds.

PCS warning light illuminates.

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

U030157*

Software Incompatibility with ECM/PCM Invalid/Incompatible Software Component

When the value of the powertrain information sent from the ECM does not match the value stored in the forward recognition camera

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the forward recognition camera is 9.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 3 seconds.

PCS warning light illuminates.

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

U032057*

Software Incompatibility with Power Steering Control Module Invalid / Incompatible Software Component

The value of the vehicle specification information sent from the power steering ECU assembly does not match the value stored in the forward recognition camera

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the forward recognition camera is 9.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 3 seconds.

PCS warning light illuminates.

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

U032251*

Software Incompatibility With Body Control Module Not Programmed

When the forward recognition camera cannot confirm the vehicle specification information based on vehicle specification information sent from the main body ECU (multiplex network body ECU)

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the forward recognition camera is 9.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 3 seconds.

PCS warning light illuminates.

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

U032257*

Software Incompatibility With Body Control Module Invalid / Incompatible Software Component

When the vehicle specification information value sent from main body ECU (multiplex network body ECU) does not match the value stored in the forward recognition camera

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the forward recognition camera is 9.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 3 seconds.

PCS warning light illuminates.

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

U110687

Lost Communication with Electric Parking Brake Module Missing Message

Communication stops between the forward recognition camera and the brake actuator assembly for approximately 5 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the forward recognition camera is 9.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 8 seconds.

-

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

U111287

Lost Communication with Combination Switch Control Module Missing Message

Communication stops between the forward recognition camera and the steering sensor for approximately 3 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the forward recognition camera is 9.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 6 seconds.

-

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

U130D57*

Instrument Panel Cluster (IPC) Control Module Invalid / Incompatible Software Component

When the vehicle specification information value sent from the combination meter assembly does not match the value stored in the forward recognition camera

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the forward recognition camera is 9.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 3 seconds.

-

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

U131457*

Software Incompatibility with Navigation Control Module Invalid / Incompatible Software Component

The AVN generation information sent from the navigation system does not match the AVN generation information stored in the forward recognition camera

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the forward recognition camera is 9.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 3 seconds.

PCS warning light illuminates.

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

(l) Blind Spot Monitor Sensor LH (B) / GTS Display "Blind Spot Monitor "B""

Body Electrical > Blind Spot Monitor "B" > Trouble Codes

HINT:

  • This ECU uses the CAN communication system for DTC communication.
  • *: Refer to Blind Spot Monitor System.

    Click here 2023 - 2025 MY Corolla Corolla Hatchback Corolla HV GR Corolla [11/2022 -        ]; PARK ASSIST / MONITORING: BLIND SPOT MONITOR SYSTEM (w/ Safe Exit Assist Function): DIAGNOSTIC TROUBLE CODE CHART

DTC

Detection Item

DTC Detection Condition

DTC Detection Pre-condition

DTC Check Procedure

Warning Displayed

DTC Storage Method

Indication in Meter

Multi-information Display

U010087

Lost Communication with ECM/PCM "A" Missing Message

Communication stops between the blind spot monitor sensor LH (B) and the ECM for approximately 11 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • Vehicle speed is 5 km/h (3 mph) or more.
  • The power source voltage of the blind spot monitor sensor LH (B) is 10.5 V or more.

Drive the vehicle at a speed of 5 km/h (3 mph) or more for approximately 14 seconds or more.

-

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

U012687

Lost Communication with Steering Angle Sensor Module Missing Message

Communication stops between the blind spot monitor sensor LH (B) and the steering sensor for approximately 11 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the blind spot monitor sensor LH (B) is 10.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 14 seconds.

-

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

U012987

Lost Communication with Brake System Control Module "A" Missing Message

Communication stops between the blind spot monitor sensor LH (B) and the brake actuator assembly for approximately 4 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the blind spot monitor sensor LH (B) is 10.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 7 seconds.

-

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

U013187

Lost Communication with Power Steering Control Module "A" Missing Message

Communication stops between the blind spot monitor sensor LH (B) and the power steering ECU with motor assembly for approximately 4 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the blind spot monitor sensor LH (B) is 10.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 7 seconds.

-

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

U014087

Lost Communication with Body Control Module Missing Message

Communication stops between the blind spot monitor sensor LH (B) and the main body ECU (multiplex network body ECU) for approximately 11 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the blind spot monitor sensor LH (B) is 10.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 14 seconds.

-

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

U023287*

Lost Communication with Side Obstacle Detection Control Module "A" Missing Message

Communication stops between the blind spot monitor sensor LH (B) and the blind spot monitor sensor RH (A) for approximately 11 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the blind spot monitor sensor LH (B) is 10.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 14 seconds.

-

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

U032251*

Software Incompatibility with Body Control Module Not Programmed

Destination information of the main body ECU (multiplex network body ECU) and blind spot monitor sensor LH (B) do not match.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the blind spot monitor sensor LH (B) is 10.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 3 seconds.

-

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

U032257*

Software Incompatibility with Body Control Module Invalid / Incompatible Software Component

Destination information of the main body ECU (multiplex network body ECU) and blind spot monitor sensor LH (B) do not match.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the blind spot monitor sensor LH (B) is 10.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 3 seconds.

-

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

U114F87

Lost Communication with Power Integration Module Missing Message

Communication stops between the blind spot monitor sensor LH (B) and the main body ECU (multiplex network body ECU) for approximately 4 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the blind spot monitor sensor LH (B) is 10.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 7 seconds.

-

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

(m) Blind Spot Monitor Sensor RH (A) / GTS Display "Blind Spot Monitor "A""

Body Electrical > Blind Spot Monitor "A" > Trouble Codes

HINT:

  • This ECU uses the CAN communication system for DTC communication.
  • *: Refer to Blind Spot Monitor System.

    Click here 2023 - 2025 MY Corolla Corolla Hatchback Corolla HV GR Corolla [11/2022 -        ]; PARK ASSIST / MONITORING: BLIND SPOT MONITOR SYSTEM (w/ Safe Exit Assist Function): DIAGNOSTIC TROUBLE CODE CHART

DTC

Detection Item

DTC Detection Condition

DTC Detection Pre-condition

DTC Check Procedure

Warning Displayed

DTC Storage Method

Indication in Meter

Multi-information Display

U023387*

Lost Communication with Side Obstacle Detection Control Module "B" Missing Message

Communication stops between the blind spot monitor sensor RH (A) and the blind spot monitor sensor LH (B) for approximately 11 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the blind spot monitor sensor RH (A) is 10 V or more.

Turn the ignition switch to ON and wait for at least approximately 14 seconds.

-

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

U032251*

Software Incompatibility with Body Control Module Not Programmed

Destination information of the main body ECU (multiplex network body ECU) and blind spot monitor sensor RH (A) do not match.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the blind spot monitor sensor RH (A) is 10 V or more.

Turn the ignition switch to ON and wait for at least approximately 3 seconds.

-

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

U032257*

Software Incompatibility with Body Control Module Invalid/Incompatible Software Component

Destination information of the main body ECU (multiplex network body ECU) and blind spot monitor sensor RH (A) do not match.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the blind spot monitor sensor RH (A) is 10 V or more.

Turn the ignition switch to ON and wait for at least approximately 3 seconds.

-

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

(n) DCM (Telematics Transceiver) / GTS Display "Telematics"

Body Electrical > Telematics > Trouble Codes

HINT:

This ECU uses the CAN communication system for DTC communication.

DTC

Detection Item

DTC Detection Condition

DTC Detection Pre-condition

DTC Check Procedure

Warning Displayed

DTC Storage Method

Indication in Meter

Multi-information Display

U014087

Lost Communication with Body Control Module Missing Message

Communication stops between the DCM (telematics transceiver) and the main body ECU (multiplex network body ECU) for approximately 10 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 10 seconds or more.
  • The power source voltage of the DCM (telematics transceiver) is 9.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 20 seconds.

-

-

DTC is stored until it is cleared using the GTS.

U015587

Lost Communication with Instrument Panel Cluster (IPC) Control Module Missing Message

Communication stops between the DCM (telematics transceiver) and the combination meter assembly for approximately 10 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 10 seconds or more.
  • The power source voltage of the DCM (telematics transceiver) is 9.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 20 seconds.

-

-

DTC is stored until it is cleared using the GTS.

U016387

Lost Communication with Navigation Control Module Missing Message

Communication stops between the DCM (telematics transceiver) and the radio and display receiver assembly for approximately 10 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 10 seconds or more.
  • The power source voltage of the DCM (telematics transceiver) is 9.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 20 seconds.

-

-

DTC is stored until it is cleared using the GTS.

(o) Radio and Display Receiver Assembly / GTS Display "Navigation System"

Body Electrical > Navigation System > Trouble Codes

HINT:

  • This ECU uses the CAN communication system for DTC communication.
  • *: Refer to Audio and Visual System.

    *1: Audio and Visual System (for Knobless Type):

    Click here 2023 - 2025 MY Corolla Corolla Hatchback Corolla HV GR Corolla [09/2022 -        ]; AUDIO / VIDEO: AUDIO AND VISUAL SYSTEM (for Knobless Radio and Display Receiver): DIAGNOSTIC TROUBLE CODE CHART

    *2: Audio and Visual System (for Single Knob Type):

    Click here 2023 - 2025 MY Corolla Corolla Hatchback Corolla HV GR Corolla [11/2022 -        ]; AUDIO / VIDEO: AUDIO AND VISUAL SYSTEM (for Single Knob Type): DIAGNOSTIC TROUBLE CODE CHART

DTC

Detection Item

DTC Detection Condition

DTC Detection Pre-condition

DTC Check Procedure

Warning Displayed

DTC Storage Method

Indication in Meter

Multi-information Display

U010087

Lost Communication with ECM/PCM "A" Missing Message

Communication stops between the radio and display receiver assembly and the ECM for approximately 11 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the radio and display receiver assembly is 9.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 14 seconds.

-

-

DTC is stored until it is cleared using the GTS.

U012987

Lost Communication with Brake System Control Module "A" Missing Message

Communication stops between the radio and display receiver assembly and the brake actuator assembly for approximately 10 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • Vehicle speed is 20 km/h (12 mph) or more.
  • The power source voltage of the radio and display receiver assembly is 9.5 V or more.

Drive the vehicle at a speed of 20 km/h (12 mph) or more for 13 seconds or more.

-

-

DTC is stored until it is cleared using the GTS.

U014087

Lost Communication with Body Control Module Missing Message

Communication stops between the radio and display receiver assembly and the main body ECU (multiplex network body ECU) for approximately 10 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the radio and display receiver assembly is 9.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 13 seconds.

-

-

DTC is stored until it is cleared using the GTS.

U015587

Lost Communication with Instrument Panel Cluster (IPC) Control Module Missing Message

Communication stops between the radio and display receiver assembly and the combination meter assembly for approximately 30 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the radio and display receiver assembly is 9.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 33 seconds.

-

-

DTC is stored until it is cleared using the GTS.

U016487

Lost Communication with HVAC Control Module Missing Message

Communication stops between the radio and display receiver assembly and the air conditioning amplifier assembly for approximately 10 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the radio and display receiver assembly is 9.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 13 seconds.

-

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

U016887

Lost Communication with Vehicle Security Control Module Missing Message

Communication stops between the radio and display receiver assembly and the certification ECU (smart key ECU assembly) for approximately 10 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the radio and display receiver assembly is 9.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 13 seconds.

-

-

DTC is stored until it is cleared using the GTS.

U019887

Lost Communication with Telematic Control Module "A" Missing Message

Communication stops between the radio and display receiver assembly and the DCM (telematics transceiver) for approximately 3 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the radio and display receiver assembly is 9.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 6 seconds.

-

-

DTC is stored until it is cleared using the GTS.

U100049*1*2

CAN Register Fixing Internal Electronic Failure

CAN communication malfunction (message register).

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the radio and display receiver assembly is 9.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 3 seconds.

-

-

DTC is stored until it is cleared using the GTS.

U11D087*2

Lost Local Communication with MET Missing Message

Communication stops between the radio and display receiver assembly and the combination meter assembly for approximately 30 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the radio and display receiver assembly is 9.5 V or more.

Turn the ignition switch to ON and wait for at least approximately 33 seconds.

-

-

DTC is stored until it is cleared using the GTS.

(p) 4WD ECU Assembly / GTS Display "Four Wheel Drive" (for G16E-GTS)

Chassis > Four Wheel Drive > Trouble Codes

HINT:

This ECU uses the CAN communication system for DTC communication.

DTC

Detection Item

DTC Detection Condition

DTC Detection Pre-condition

DTC Check Procedure

Warning Displayed

DTC Storage Method

Indication in Meter

Multi-information Display

U010087

Lost Communication with ECM/PCM "A" Missing Message

Communication stops between the 4WD ECU assembly and the ECM for approximately 5 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the 4WD ECU assembly is 10 V or more.

Turn the ignition switch to ON and wait for at least approximately 8 seconds.

-

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

U012687

Lost Communication with Steering Angle Sensor Module Missing Message

Either of the following conditions is met:

  • Communication stops between the 4WD ECU assembly and the steering sensor for approximately 2 seconds or more.
  • Condition occurs 10 times or more within 60 seconds:
    • The 4WD ECU assembly does not receive data from the steering sensor once or more within 5 seconds.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the 4WD ECU assembly is 10 V or more.

Turn the ignition switch to ON and wait for at least approximately 63 seconds.

-

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

U012987

Lost Communication with Brake System Control Module Missing Message

Communication stops between the 4WD ECU assembly and the brake actuator assembly for approximately 4 seconds or more.

All conditions are met:

  • The ignition switch is ON for approximately 3 seconds or more.
  • The power source voltage of the 4WD ECU assembly is 10 V or more.

Turn the ignition switch to ON and wait for at least approximately 7 seconds.

-

Displays messages on the multi-information display.

DTC is stored until it is cleared using the GTS.

(q) Airbag Sensor Assembly / GTS Display "SRS Airbag"

Body Electrical > SRS Airbag > Trouble Codes

HINT:

This ECU uses the CAN communication system for DTC communication.

DTC

Detection Item

DTC Detection Condition

DTC Detection Pre-condition

DTC Check Procedure

Warning Displayed

DTC Storage Method

Indication in Meter

Multi-information Display

U012987

Lost Communication with Brake System Control Module "A" Missing Message

Communication stops between the airbag sensor assembly and the brake actuator assembly for approximately 5 seconds or more.

The ignition switch is ON for approximately 3 seconds or more.

Turn the ignition switch to ON and wait for at least approximately 8 seconds.

SRS warning light illuminates.

-

DTC is stored until it is cleared using the GTS.

U023A87

Lost Communication with Image Processing Module "A" Missing Message

Communication stops between the airbag sensor assembly and the forward recognition camera for approximately 10 seconds or more.

The ignition switch is ON for approximately 3 seconds or more.

Turn the ignition switch to ON and wait for at least approximately 13 seconds.

SRS warning light illuminates.

-

DTC is stored until it is cleared using the GTS.

(r) Tire Pressure Warning ECU and Receiver / GTS Display "Tire Pressure Monitor"

Chassis > Tire Pressure Monitor > Trouble Codes

HINT:

This ECU uses the CAN communication system for DTC communication.

DTC

Detection Item

DTC Detection Condition

DTC Detection Pre-condition

DTC Check Procedure

Warning Displayed

DTC Storage Method

Indication in Meter

Multi-information Display

U012987

Lost Communication with Brake System Control Module "A" Missing Message

Communication stops between the tire pressure warning ECU and receiver and the brake actuator assembly for approximately 60 seconds or more.

The ignition switch is ON for approximately 1 second or more.

Turn the ignition switch to ON and wait for at least approximately 61 seconds.

-

-

DTC is stored until it is cleared using the GTS.

(s) Central Gateway ECU (Network Gateway ECU) / GTS Display "Central Gateway"

Body Electrical > Central Gateway > Trouble Codes

HINT:

The central gateway ECU (network gateway ECU) is connected to the CAN communication system, but the central gateway ECU (network gateway ECU) does not store or output CAN communication DTCs.

(t) Steering Sensor / GTS Display "Steering Angle Sensor"

Chassis > Steering Angle Sensor > Trouble Codes

HINT:

The steering sensor is connected to the CAN communication system, but the steering sensor does not store or output CAN communication DTCs.

CAN BUS WAVEFORMS

HINT:

  • This waveform is measured between terminals CANH and GND, and terminals CANL and GND of the central gateway ECU (network gateway ECU). (Use this as a reference for diagnosis of CAN communication lines.)
  • When malfunctions in multiple ECUs are suspected based on the CAN bus check and DTCs checked using the GTS, check the resistance of the CAN bus using an ohmmeter first. If no problems are found, check the following waveforms.
  • If a waveform is not similar to one of the following 3 patterns (Group 1), then an open in a CAN main bus line, an open in a CAN branch line, or a short between a CAN line (CANH or CANL) and ground is suspected (Group 2).
  • Wiggle the connector and wire harness to check if the waveform changes.

(a) CAN bus waveforms (Group 1)

(1) Normal waveform

(2) Open in both of the lines (CANH and CANL) of a CAN branch

HINT:

  • Waveforms (waveforms shown using dotted lines) are not output from an ECU or sensor connected to a CAN branch with an open circuit in both lines. (Waveforms from other ECUs or sensors are normal.)
  • Because this waveform is similar to a normal waveform, instead of using the waveform, the malfunctioning part can be narrowed down by performing a CAN bus check.

(3) Short between the CAN bus lines (CANH and CANL)

HINT:

  • Waveforms disappear.
  • If the malfunction is in an ECU, disconnecting the ECU will change the waveform. If the waveform does not change, a malfunction in the wire harness is suspected.

(b) CAN bus waveforms (reference) (Group 2)

NOTICE:

The following CAN bus waveforms can be used only as reference. The actual measured waveform may differ significantly depending on the location of the open or short circuit.

(1) Open in a CAN branch line (CANH)

HINT:

  • An abnormal waveform is output from an ECU with an open in one of its CAN branch lines. Because this abnormal output interferes with the signals from other ECUs, the output of other ECUs will also appear abnormal.
  • Narrow down the malfunctioning part by checking DTCs or performing a CAN bus check, or by checking waveform changes when ECUs or sensors are disconnected. The waveform will change to one for an open in both sides of a CAN branch when the ECU or sensor with an open CAN branch line is disconnected.

(2) Open in a CAN branch line (CANL)

HINT:

  • An abnormal waveform is output from an ECU with an open in one of its CAN branch lines. Because this abnormal output interferes with the signals from other ECUs, the output of other ECUs will also appear abnormal.
  • Narrow down the malfunctioning part by checking DTCs or performing a CAN bus check, or by checking waveform changes when ECUs or sensors are disconnected. The waveform will change to one for an open in both sides of a CAN branch when the ECU or sensor with an open CAN branch line is disconnected.

(3) Open in a CAN main bus line (CANH)

HINT:

  • Waveforms of ECUs or sensors that are closer to the central gateway ECU (network gateway ECU) than the open part are almost normal.
  • Waveforms of ECUs or sensors that are on the opposite side of the central gateway ECU (network gateway ECU) from the open part are abnormal.
  • An open in a CAN main bus line can be confirmed by measuring the resistance between the CANH and CANL terminals of any CAN branch.

(4) Short between a CAN bus line (CANH) and ground

HINT:

  • Narrow down the shorted part by checking for waveform changes when disconnecting connectors from the CAN junction connectors or when disconnecting ECUs or sensors.
  • A short to ground in the CANH line can be confirmed by measuring the resistance between CANH and ground using an ohmmeter.

(5) Short between a CAN bus line (CANL) and ground

HINT:

  • Narrow down the shorted part by checking for waveform changes when disconnecting connectors from the CAN junction connectors or when disconnecting ECUs or sensors.
  • A short to ground in the CANL line can be confirmed by measuring the resistance between CANL and ground using an ohmmeter.