Toyota Corolla Cross: Lost Communication with Brake System Control Module Missing Message (U012987)
MONITOR DESCRIPTION
The ECM and skid control ECU (brake actuator assembly) send and receive signals via CAN communication.
If a communication error occurs between the ECM and skid control ECU (brake actuator assembly), the ECM stores this DTC.
DTC No. | Detection Item |
DTC Detection Condition | Trouble Area |
MIL | Note |
U012987 | Lost Communication with Brake System Control Module Missing Message |
All of the following conditions are met for 2.2 seconds or more (1 trip detection logic):
- Ignition switch ON
- Auxiliary battery voltage is 10 V or higher
- No communication between ECM and skid control ECU (brake actuator assembly)
|
- CAN communication system
- Skid control ECU (brake actuator assembly)
- ECM
| Does not come on |
- SAE Code: U0129
- DTC for Mexico Models: Applies
|
MONITOR STRATEGY
Frequency of Operation | Continuous |
CONFIRMATION DRIVING PATTERN
HINT:
- Connect the GTS to the DLC3.
- Turn the ignition switch to ON.
- Turn the GTS on.
- Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
- Turn the ignition switch off and wait for at least 30 seconds.
- Turn the ignition switch to ON [A].
- Turn the GTS on.
- Wait 5 seconds or more.
- Enter the following menus: Powertrain / Engine / Trouble Codes [B].
- Read the pending DTCs.
HINT:
- If a pending DTC is output, the system is malfunctioning.
- If a pending DTC is not output, perform the following procedure.
- Enter the following menus: Powertrain / Engine / Utility / All Readiness.
- Input the DTC: U012987.
- Check the DTC judgment result.
GTS Display |
Description |
NORMAL |
- DTC judgment completed
- System normal
|
ABNORMAL |
- DTC judgment completed
- System abnormal
|
INCOMPLETE |
- DTC judgment not completed
- Perform driving pattern after confirming DTC enabling conditions
|
HINT:
CAUTION / NOTICE / HINT
HINT:
Read freeze frame data using the GTS. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air fuel ratio was lean or rich, and other data from the time the malfunction occurred.
PROCEDURE
1. |
CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC U012987) |
(a) Read the DTCs.
Result | Proceed to |
DTC U012987 is output |
A |
DTC U012987 and other DTCs are output |
B |
HINT:
If any DTCs other than U012987 are output, troubleshoot those DTCs first.
B |
| GO TO DTC CHART |
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DESCRIPTION The ECM and skid control ECU (brake actuator assembly) send and receive signals via CAN communication.
If a communication error occurs between the ECM and skid control ECU (brake actuato
SEE MORE:
DCM ACTIVATION
DCM ACTIVATION
(a) Enter the following menus:
Body Electrical > Telematics > Utility
Tester Display
VIN Synchronization
(b) According to the display on the GTS, read the IMEI, ICCID,
software version and VIN.
(c) Turn the ignition swi
REMOVAL CAUTION / NOTICE / HINT COMPONENTS (REMOVAL)
Procedure Part Name Code
1 AIR CONDITIONER UNIT ASSEMBLY
- -
- -
2 TRANSPONDER KEY ECU ASSEMBLY
89780 -
- - CAUTION / NOTICE / HINT
The necessary procedures (adj