U0101

U0101-LOST COMMUNICATION WITH TCM



- When Monitored:
With the ignition on.

Battery voltage between 10 and 16 volts.

Ignition Off Draw (IOD) fused installed.

Totally Integrated Power Module (TIPM) is configured correctly.

- Set Condition:
Bus messages not received from the TCM for approximately two to five seconds.





1. VERIFY DTC IS ACTIVE

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

1. With the scan tool, read active DTCs.

Is this DTC active?

Yes

- Go To 2

No

- Stored Lost Communication DTCs Perform the Stored Lost Communication DTCs diagnostic procedure.

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

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

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

Yes

- Go to and perform the appropriate diagnostic procedure.

No

- Go To 3

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

Is the TCM active on the bus?

Yes

- Go To 4

No

- No Response From TCM (Powertrain Control Module) - NGC Perform the No Response from TCM diagnostic procedure.

4. CHECK FOR ADDITIONAL COMMUNICATION RELATED DTCS
1. With the scan tool, select Network Diagnostics.

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

Yes

- Replace/update the TCM (PCM).
- Perform the appropriate TRANSMISSION VERIFICATION TEST. 40/41TE Transmission Verification Test.

No

- Replace the Anti-Lock Brake Module.
- Perform the ABS VERIFICATION TEST. ABS Verification Test.