Antilock Brake Module (ABS)

U0101-LOST COMMUNICATION WITH TCM

For a complete wiring diagram, refer to the Wiring Information.

- When Monitored:

- With the ignition on
- Battery voltage between 10 and 16 volts
- IOD fuse installed
- Set Condition:
If the Anti-Lock Brakes System (ABS) Module fails to receive bus messages from the Transmission Control Module (TCM) for approximately 500 ms.





1. VERIFY DTC IS ACTIVE

NOTE: Verify the IOD fuse is installed and battery voltage is between 10 and 16 volts before proceeding.

NOTE: If present, diagnose and repair DTC U0002-CAN C BUS OFF PERFORMANCE, DTC U0146-LOST COMMUNICATION WITH CENTRAL GATEWAY, or DTC U1502-IMPLAUSIBLE MESSAGE DATA LENGTH RECEIVED FROM FCM / BCM before diagnosing this DTC.

1. Ignition on, engine not running.
2. With the scan tool, read and record ABS DTCs.
3. With the scan tool, read and record Environmental Data (EV Data).
4. With the scan tool, erase ABS DTCs.
5. Cycle the ignition switch.
6. With the scan tool, read ABS DTCs.

Does this DTC reset?

Yes

- Go To 2

No

- Perform the Stored Lost Communication test procedure.
- Perform BODY VERIFICATION TEST. Body Verification Test

2. CHECK FOR ANY OF THE FOLLOWING ACTIVE DTCs
1. With the scan tool, read all active DTCs from all CAN C Bus modules.

NOTE: Check for CAN C hardware electrical, VIN Missing/Mismatch, battery or ignition related DTCs.

Does the scan tool display any active DTCs related to the conditions listed above?

Yes

- Diagnose and repair the DTCs.

No

- Go To 3

3. VERIFY THAT THE TCM IS ACTIVE ON THE BUS
1. With the scan tool, select ECU View.
2. Verify that the TCM is active on the bus.

Is the TCM active on the bus?

Yes

- Go To 4

No

- Perform the Stored Lost Communication test procedure.
- Perform BODY VERIFICATION TEST. Body Verification Test

4. CHECK FOR ADDITIONAL COMMUNICATION RELATED DTCs
1. With the scan tool, select Network View and select Advanced.

Is there more than one module with active DTCs "Logged Against" the TCM?

Yes

- Replace/update the Transmission Control Module (TCM).
- Perform TCM VERIFICATION TEST. Verification Tests.

No

- Replace the Anti-Lock Brakes System (ABS) Module.
- Perform ABS VERIFICATION TEST. ABS Verification Test.