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 9.0 and 16.0 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.





ACTIVE DTC
1. Ignition on, engine not running.
2. With a scan tool, read PCM DTCs.

Is the DTC active at this time?

Yes

- Totally Integrated Power Module (TIPM) Perform the U0121-Lost Communication with Anti-lock Brake Module diagnostic procedure.

No

- Perform the Stored Lost Communication DTCs diagnostic procedure.