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Shorted Communication Line Test

Shorted Communication Line Test

Special Tools Required
MFCS service connector 07WAZ-001010A

1. Remove the driver's multiplex control unit from the driver's under-dash fuse/relay box.
2. Carefully pry oft the driver's door switch trim
3. Disconnect door multiplex connector A (20P).
4. Disconnect passenger's multiplex control unit connector B (22P).




5. Check for continuity between No. 15 terminal of door multiplex connector A (20P) and body ground.

Is there continuity?

YES - Repair short to ground in the wire between door multiplex control unit connector and body ground.

NO - Go to step 6.




6. Check for continuity between B9 terminal of passenger's multiplex connector B (22P) and body ground.

Is there continuity?

YES - Repair short to ground in the wire between passenger's multiplex control unit connector and driver's multiplex control unit connector.

NO - Replace driver's multiplex control unit and recheck the symptom.