Diagnostic Test

1) ACTIVE DTC
Ignition on, engine not running.

With the scan tool, view PCM DTCs.

Is the DTC Active at this time?

Yes
1. Go to 2).
No
1. Refer to INTERMITTENT CONDITION Diagnostic Procedure.
2) U0121-LOST COMMUNICATION WITH ABS MODULE ALSO SET
With the scan tool continue reading DTCs.

Is the U0121-LOST COMMUNICATION WITH ABS MODULE also set?

Yes
1. Follow the diagnostics for U0121-LOST COMMUNICATION WITH ANTI-LOCK BRAKE MODULE .
No
1. Replace and program the Powertrain Control Module per Service Information.
2. Perform POWERTRAIN VERIFICATION TEST .