Last Modified: 05-13-2024 6.11:8.1.0 Doc ID: RM10000000259PY
Model Year Start: 2023 Model: Corolla Prod Date Range: [09/2022 - 11/2022]
Title: NETWORKING: CAN COMMUNICATION SYSTEM (for HV Model): Main Body ECU Communication Stop Mode; 2023 MY Corolla Corolla HV [09/2022 - 11/2022]

Main Body ECU Communication Stop Mode

DESCRIPTION

Detection Item

Symptom

Trouble Area

Main Body ECU Communication Stop Mode

Communication stop for "Main Body" is indicated on the "Communication Bus Check" screen of the GTS.

2023 MY Corolla Corolla HV [09/2022 - 11/2022]; NETWORKING: CAN COMMUNICATION SYSTEM (for HV Model): DIAGNOSIS SYSTEM

  • Main body ECU (multiplex network body ECU) main line or connector
  • Power source circuit of main body ECU (multiplex network body ECU) or power distribution box assembly
  • Main body ECU (multiplex network body ECU) or power distribution box assembly ground circuit
  • Main body ECU (multiplex network body ECU) or power distribution box assembly

WIRING DIAGRAM

CAUTION / NOTICE / HINT

CAUTION:

When performing the confirmation driving pattern, obey all speed limits and traffic laws.

NOTICE:

  • Because the order of diagnosis is important to allow correct diagnosis, make sure to begin troubleshooting using How to Proceed with Troubleshooting when CAN communication system related DTCs are output.

    Click here 2023 - 2025 MY Corolla Corolla HV [09/2022 -        ]; NETWORKING: CAN COMMUNICATION SYSTEM (for HV Model): HOW TO PROCEED WITH TROUBLESHOOTING

  • Before measuring the resistance of the CAN bus, turn the ignition switch off and leave the vehicle for 1 minute or more without operating the key or any switches, or opening or closing the doors. After that, disconnect the cable from the negative (-) auxiliary battery terminal and leave the vehicle for 1 minute or more before measuring the resistance.
  • After the ignition switch is turned off, there may be a waiting time before disconnecting the negative (-) auxiliary battery terminal.

    Click here 2023 - 2025 MY Corolla Corolla Hatchback Corolla HV GR Corolla [09/2022 -        ]; SETUP: WHEN DISCONNECTING OR RECONNECTING BATTERY TERMINAL: BEFORE DISCONNECTING BATTERY

  • When disconnecting and reconnecting the auxiliary battery.

    HINT:

    When disconnecting and reconnecting the auxiliary battery, there is an automatic learning function that completes learning when the respective system is used.

    Click here 2023 MY Corolla Corolla Hatchback Corolla HV GR Corolla [09/2022 - 11/2022]; SETUP: WHEN DISCONNECTING OR RECONNECTING BATTERY TERMINAL: AUTOMATIC LEARNING CHART

  • Some parts must be initialized and set when replacing or removing and installing parts.

    Click here 2023 MY Corolla Corolla Hatchback Corolla HV GR Corolla [09/2022 - 11/2022]; SETUP: WHEN REPLACING OR REMOVING/INSTALLING PARTS: WORK PROCEDURE

  • After performing repairs, perform the DTC check procedure and confirm that the DTCs are not output again.

    DTC check procedure: Turn the ignition switch to ON and wait for 1 minute or more. Then operate the suspected malfunctioning system and drive the vehicle at 60 km/h (37 mph) or more for 5 minutes or more.

  • After the repair, perform the CAN bus check and check that all the ECUs and sensors connected to the CAN communication system are displayed as normal.

    Click here 2023 MY Corolla Corolla HV [09/2022 - 11/2022]; NETWORKING: CAN COMMUNICATION SYSTEM (for HV Model): DIAGNOSIS SYSTEM

  • Inspect the fuses for circuits related to this system before performing the following procedure.
  • Before replacing the main body ECU (multiplex network body ECU), refer to Registration.

    Click here 2023 - 2025 MY Corolla Corolla HV [09/2022 -        ]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, HV Model): REGISTRATION

HINT:

  • Before disconnecting related connectors for inspection, push in on each connector body to check that the connector is not loose or disconnected.
  • When a connector is disconnected, check that the terminals and connector body are not cracked, deformed or corroded.

PROCEDURE

1.

CHECK FOR OPEN IN CAN BUS LINES (MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) MAIN LINE)

(a) Disconnect the cable from the negative (-) auxiliary battery terminal.

(b) Disconnect the I85 main body ECU (multiplex network body ECU) connector.

(c) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

I85-2 (CANH) - I85-1 (CANL)

Cable disconnected from negative (-) auxiliary battery terminal

108 to 132 Ω

*a

Front view of wire harness connector

(to Main Body ECU (Multiplex Network Body ECU))

NG

REPAIR OR REPLACE CAN MAIN BUS LINES OR CONNECTOR (MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU))

OK

2.

CHECK HARNESS AND CONNECTOR (POWER SOURCE CIRCUIT)

(a) Remove the main body ECU (multiplex network body ECU).

Click here 2023 MY Corolla Corolla Hatchback Corolla HV GR Corolla [09/2022 - 11/2022]; POWER DISTRIBUTION: MAIN BODY ECU: REMOVAL

(b) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

MB-13 (GND1) - Body ground

Cable disconnected from negative (-) auxiliary battery terminal

Below 1 Ω

MB-14 (GND2) - Body ground

Cable disconnected from negative (-) auxiliary battery terminal

Below 1 Ω

NOTICE:

Perform this inspection with the wire harness connected to the power distribution box assembly.

*1

Power Distribution Box Assembly

(c) Reconnect the cable to the negative (-) auxiliary battery terminal.

(d) Measure the voltage according to the value(s) in the table below.

Standard Voltage:

Tester Connection

Condition

Specified Condition

MB-26 (BECU) - Body ground

Ignition switch off

11 to 14 V

NOTICE:

Perform this inspection with the wire harness connected to the power distribution box assembly.

Result

Proceed to

OK

A

NG (BECU)

B

NG (GND1 or GND2)

C

A

CHECK ECU POWER SOURCE CIRCUIT

C

GO TO STEP 4

B

3.

CHECK HARNESS AND CONNECTOR (BECU SIGNAL CIRCUIT)

(a) Disconnect the cable from the negative (-) auxiliary battery terminal.

(b) Disconnect the 8F power distribution box assembly connector.

(c) Reconnect the cable to the negative (-) auxiliary battery terminal.

(d) Measure the voltage according to the value(s) in the table below.

Standard Voltage:

Tester Connection

Condition

Specified Condition

8F-23 - Body ground

Ignition switch off

11 to 14 V

*a

Front view of wire harness connector

(to Power Distribution Box Assembly)

OK

REPLACE POWER DISTRIBUTION BOX ASSEMBLY

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR (BECU SIGNAL CIRCUIT)

4.

CHECK HARNESS AND CONNECTOR (GROUND CIRCUIT)

(a) Disconnect the cable from the negative (-) auxiliary battery terminal.

(b) Disconnect the 8D power distribution box assembly connector.

(c) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

8D-1 - Body ground

Cable disconnected from negative (-) auxiliary battery terminal

Below 1 Ω

*a

Front view of wire harness connector

(to Power Distribution Box Assembly)

OK

REPLACE POWER DISTRIBUTION BOX ASSEMBLY

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR (GROUND CIRCUIT)