EATX PRNDL Message Test Failed

SYMPTOM
EATX PRNDL MESSAGE TEST FAILED

WHEN MONITORED
When engine is running.

SET CONDITION
The engine is running above 450 rpm and the Body Control Module has not received a transmission PRNDL message.

POSSIBLE CAUSES
- Transaxle operates improperly
- CCD bus (+) circuit open
- CCD bus (-) circuit open
- TCM doesn't communicate