Diagnostic Test
- ACTIVE DTC NOTE:
For vehicle communication problems, use the scan tool to refer to the Network Review Screen. The screen depicts a high level view of the vehicle network. Fault and problem areas appear in red. Selecting any of the network components allows access to the source of the problem.
- Ignition on, engine not running.
- With a scan tool, select View DTCs.
Is the status Active for this DTC?
Yes
- Go To 2
No
- Perform the INTERMITTENT CONDITION diagnostic procedure. Refer to the appropriate Testing & Diagnostics article under Engine Performance .
- U0121-LOST COMMUNICATION WITH ANTI-LOCK BRAKE SYSTEM (ABS) CONTROL MODULE ALSO SET
- With a scan tool, select View DTCs.
Is the DTC U0121-LOST COMMUNICATION WITH ANTI-LOCK BRAKE SYSTEM (ABS) CONTROL MODULE OR ANY LOST COMMUNICATION DTCS also set?
Yes
- Refer to DIAGNOSTIC CODE INDEX and perform the U0140-00-Lost Communication with BCM diagnostic procedure.
No
- Replace and program the Powertrain Control Module (PCM) in accordance with the Service Information. Refer to MODULE, POWERTRAIN CONTROL, REMOVAL .
- Perform the PCM/POWERTRAIN VERIFICATION TEST. Refer to the appropriate Testing & Diagnostics article under Engine Performance .
- With a scan tool, select View DTCs.