- Short to +B in CAN branch line
- Short to +B in CAN branch line
- Central gateway ECU (network gateway ECU)
- Steering sensor
- Airbag sensor assembly
- Occupant Detection ECU
- Power steering ECU with motor assembly
- Brake actuator assembly
-
No. 5 CAN junction connector
(for Hatchback)
-
No. 4 CAN junction connector
(for Sedan)
-
No. 1 junction connector
(for Sedan)
| Last Modified: 05-13-2024 | 6.11:8.1.0 | Doc ID: RM100000001GMBD |
| Model Year Start: 2020 | Model: GR Corolla | Prod Date Range: [01/2019 - 09/2022] |
| Title: NETWORKING: CAN COMMUNICATION SYSTEM (for Gasoline Model): Check Bus 4 Line for Short to +B; 2020 - 2022 MY Corolla Corolla Hatchback GR Corolla [01/2019 - 09/2022] | ||
|
Check Bus 4 Line for Short to +B |
DESCRIPTION
There may be a short circuit between one of the CAN bus lines and +B when there is no resistance between terminal 22 (CA2H) of the central gateway ECU (network gateway ECU) and terminal 16 (BAT) of the DLC3, or terminal 7 (CA2L) of the central gateway ECU (network gateway ECU) and terminal 16 (BAT) of the DLC3.
|
Symptom |
Trouble Area |
|---|---|
|
There is no resistance between terminal 22 (CA2H) of the central gateway ECU (network gateway ECU) and terminal 16 (BAT) of the DLC3, or terminal 7 (CA2L) of the central gateway ECU (network gateway ECU) and terminal 16 (BAT) of the DLC3. |
|
WIRING DIAGRAM
for Hatchback
for Sedan
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.
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![2019 - 2022 MY Corolla Corolla Hatchback GR Corolla [06/2018 - 09/2022]; NETWORKING: CAN COMMUNICATION SYSTEM (for Gasoline Model): HOW TO PROCEED WITH TROUBLESHOOTING](/t3Portal/stylegraphics/info.gif)
- 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 (-) battery terminal and leave the vehicle for 1 minute or more before measuring the resistance.
-
After turning the ignition switch off, waiting time may be required before disconnecting the cable from the negative (-) battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) battery terminal notices before proceeding with work.
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-
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.
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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 VEHICLE TYPE |
(a) Check vehicle type.
|
Result |
Proceed to |
|---|---|
|
for Hatchback |
A |
|
for Sedan |
B |
| B |
|
|
|
2. |
CHECK FOR SHORT TO +B IN CAN BUS LINE (NO. 5 CAN JUNCTION CONNECTOR) |
(a) Disconnect the cable from the negative (-) battery terminal.
(b) Disconnect the I96 No. 5 CAN junction connector.
(c) Measure the resistance according to the value(s) in the table below.
|
*1 |
DLC3 |
- |
- |
|
*a |
Front view of wire harness connector (to No. 5 CAN Junction Connector) |
*b |
to Steering Sensor |
|
*c |
to Central Gateway ECU (Network Gateway ECU) |
*d |
to Airbag Sensor Assembly |
|
*e |
to Occupant Detection ECU |
*f |
to Power Steering ECU with Motor Assembly |
|
*g |
to Brake Actuator Assembly |
- |
- |
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
Connected to |
|---|---|---|---|
|
I96-1 (CANH) - I26-16 (BAT) |
Cable disconnected from negative (-) battery terminal |
6 kΩ or higher |
Steering sensor |
|
I96-7 (CANL) - I26-16 (BAT) |
|||
|
I96-2 (CANH) - I26-16 (BAT) |
Cable disconnected from negative (-) battery terminal |
6 kΩ or higher |
Central gateway ECU (network gateway ECU) |
|
I96-8 (CANL) - I26-16 (BAT) |
|||
|
I96-3 (CANH) - I26-16 (BAT) |
Cable disconnected from negative (-) battery terminal |
6 kΩ or higher |
Airbag sensor assembly |
|
I96-9 (CANL) - I26-16 (BAT) |
|||
|
I96-4 (CANH) - I26-16 (BAT) |
Cable disconnected from negative (-) battery terminal |
6 kΩ or higher |
Occupant detection ECU |
|
I96-10 (CANL) - I26-16 (BAT) |
|||
|
I96-5 (CANH) - I26-16 (BAT) |
Cable disconnected from negative (-) battery terminal |
6 kΩ or higher |
Power steering ECU with motor assembly |
|
I96-11 (CANL) - I26-16 (BAT) |
|||
|
I96-6 (CANH) - I26-16 (BAT) |
Cable disconnected from negative (-) battery terminal |
6 kΩ or higher |
Brake actuator assembly |
|
I96-12 (CANL) - I26-16 (BAT) |
|
Result |
Proceed to |
|---|---|
|
OK |
A |
|
NG (Line to central gateway ECU (network gateway ECU)) |
B |
|
NG (Line to ECU or sensor) |
C |
| A |
|
REPLACE NO. 5 CAN JUNCTION CONNECTOR |
| C |
|
|
|
3. |
CHECK FOR SHORT TO +B IN CAN BUS LINE (NO. 5 CAN JUNCTION CONNECTOR - CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU)) |
(a) Disconnect the I53 central gateway ECU (network gateway ECU) connector.
(b) Measure the resistance according to the value(s) in the table below.
|
*1 |
DLC3 |
- |
- |
|
*a |
Front view of wire harness connector (to No. 5 CAN Junction Connector) |
*b |
to Central Gateway ECU (Network Gateway ECU) |
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
I96-2 (CANH) - I26-16 (BAT) |
Cable disconnected from negative (-) battery terminal |
6 kΩ or higher |
|
I96-8 (CANL) - I26-16 (BAT) |
| OK |
|
| NG |
|
REPAIR OR REPLACE CAN MAIN BUS LINE OR CONNECTOR (NO. 5 CAN JUNCTION CONNECTOR - CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU)) |
|
4. |
CHECK FOR SHORT TO +B IN CAN BUS LINE (NO. 1 JUNCTION CONNECTOR) |
(a) Disconnect the cable from the negative (-) battery terminal.
(b) Disconnect the O118 No. 1 junction connector.
(c) Measure the resistance according to the value(s) in the table below.
|
*1 |
DLC3 |
- |
- |
|
*a |
Front view of wire harness connector (to No. 1 Junction Connector) |
*b |
to Central Gateway ECU (Network Gateway ECU) |
|
*c |
to Occupant Detection ECU |
*d |
to No. 4 CAN Junction Connector |
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
Connected to |
|---|---|---|---|
|
O118-9 (CANH) - I26-16 (BAT) |
Cable disconnected from negative (-) battery terminal |
6 kΩ or higher |
Central gateway ECU (network gateway ECU) |
|
O118-20 (CANL) - I26-16 (BAT) |
|||
|
O118-10 (CANH) - I26-16 (BAT) |
Cable disconnected from negative (-) battery terminal |
6 kΩ or higher |
Occupant detection ECU |
|
O118-21 (CANL) - I26-16 (BAT) |
|||
|
O118-11 (CANH) - I26-16 (BAT) |
Cable disconnected from negative (-) battery terminal |
6 kΩ or higher |
No. 4 CAN junction connector |
|
O118-22 (CANL) - I26-16 (BAT) |
|
Result |
Proceed to |
|---|---|
|
OK |
A |
|
NG (Line to central gateway ECU (network gateway ECU)) |
B |
|
NG (Line to No. 4 CAN junction connector) |
C |
|
NG (Line to ECU or sensor) |
D |
| A |
|
REPLACE NO. 1 JUNCTION CONNECTOR |
| C |
|
| D |
|
|
|
5. |
CHECK FOR SHORT TO +B IN CAN BUS LINE (NO. 1 JUNCTION CONNECTOR - CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU)) |
(a) Disconnect the I53 central gateway ECU (network gateway ECU) connector.
(b) Measure the resistance according to the value(s) in the table below.
|
*1 |
DLC3 |
- |
- |
|
*a |
Front view of wire harness connector (to No. 1 Junction Connector) |
*b |
to Central Gateway ECU (Network Gateway ECU) |
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
O118-9 (CANH) - I26-16 (BAT) |
Cable disconnected from negative (-) battery terminal |
6 kΩ or higher |
|
O118-20 (CANL) - I26-16 (BAT) |
| OK |
|
| NG |
|
REPAIR OR REPLACE CAN MAIN BUS LINE OR CONNECTOR (NO. 1 JUNCTION CONNECTOR - CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU)) |
|
6. |
CHECK FOR SHORT TO +B IN CAN BUS LINE (NO. 4 CAN JUNCTION CONNECTOR) |
(a) Disconnect the I95 No. 4 CAN junction connector.
(b) Measure the resistance according to the value(s) in the table below.
|
*1 |
DLC3 |
- |
- |
|
*a |
Front view of wire harness connector (to No. 4 CAN Junction Connector) |
*b |
to Steering Sensor |
|
*c |
to Airbag Sensor Assembly |
*d |
to No. 1 Junction Connector |
|
*e |
to Power Steering ECU with Motor Assembly |
*f |
to Brake Actuator Assembly |
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
Connected to |
|---|---|---|---|
|
I95-1 (CANH) - I26-16 (BAT) |
Cable disconnected from negative (-) battery terminal |
6 kΩ or higher |
Steering sensor |
|
I95-12 (CANL) - I26-16 (BAT) |
|||
|
I95-3 (CANH) - I26-16 (BAT) |
Cable disconnected from negative (-) battery terminal |
6 kΩ or higher |
Airbag sensor assembly |
|
I95-14 (CANL) - I26-16 (BAT) |
|||
|
I95-4 (CANH) - I26-16 (BAT) |
Cable disconnected from negative (-) battery terminal |
6 kΩ or higher |
No. 1 junction connector |
|
I95-15 (CANL) - I26-16 (BAT) |
|||
|
I95-5 (CANH) - I26-16 (BAT) |
Cable disconnected from negative (-) battery terminal |
6 kΩ or higher |
Power steering ECU with motor assembly |
|
I95-16 (CANL) - I26-16 (BAT) |
|||
|
I95-6 (CANH) - I26-16 (BAT) |
Cable disconnected from negative (-) battery terminal |
6 kΩ or higher |
Brake actuator assembly |
|
I95-17 (CANL) - I26-16 (BAT) |
|
Result |
Proceed to |
|---|---|
|
OK |
A |
|
NG (Line to No. 1 junction connector) |
B |
|
NG (Line to ECU or sensor) |
C |
| A |
|
REPLACE NO. 4 CAN JUNCTION CONNECTOR |
| B |
|
REPAIR OR REPLACE CAN MAIN BUS LINE OR CONNECTOR (NO. 4 CAN JUNCTION CONNECTOR - NO. 1 JUNCTION CONNECTOR) |
| C |
|
|
7. |
CHECK FOR SHORT TO +B IN CAN BUS LINE (ECU OR SENSOR) |
(a) Reconnect all wire harness connectors.
(b) Disconnect the connector that includes terminals CANH and CANL from the ECU or sensor to which the bus line shorted to +B is connected.
Click here
(c) Measure the resistance according to the value(s) in the table below.
|
*1 |
DLC3 |
- |
- |
|
*a |
Component with harness connected (Central Gateway ECU (Network Gateway ECU)) |
- |
- |
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
I53-22 (CA2H) - I26-16 (BAT) |
Cable disconnected from negative (-) battery terminal |
6 kΩ or higher |
|
I53-7 (CA2L) - I26-16 (BAT) |
HINT:
- If the resistance changes to 6 kΩ or higher when the connector is disconnected from the ECU or sensor, there may be a short in the ECU or sensor.
- If the resistance does not become normal when the connector is disconnected from the ECU or sensor, check for a short to +B in the wire harness and repair or replace the wire harness or connector if necessary.
| OK |
|
REPLACE ECU OR SENSOR |
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
|