Powertrain Control Module (PCM)

U0121-LOST COMMUNICATION WITH ANTI-LOCK BRAKE MODULE

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

- When Monitored:
Ignition run time is greater than one second. Battery voltage between 9 and 16 volts. Engine run time greater than three seconds.

- Set Condition:
The Powertrain Control Module (PCM) doesn't receive an ABS message over the CAN C circuit for seven consecutive seconds. The circuit is continuously monitored.





Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. PCM Pre-Diagnostic Troubleshooting Procedure.

Diagnostic Test
ACTIVE DTC
1. Ignition on, engine not running.
2. With a scan tool, select View DTCs.

Is the status Active for this DTC?

Yes

- Totally Integrated Power Module (TIPM) and perform the U0121-Lost Communication with Anti-Lock Brake Module diagnostic procedure.

No

- Perform the CHECKING FOR AN INTERMITTENT DTC diagnostic procedure. PCM Intermittent Condition Test.