Shorted Communication Line Test
Shorted Communication Line Test1. Remove the driver's multiplex control unit from the driver's under-dash fuse/relay box.
2. Carefully pry off the driver's door switch trim.
3. Disconnect door multiplex control unit connector A (20P).
4. Disconnect passenger's multiplex control unit connector B (22P).
5. Check for continuity between the No.15 terminal of door multiplex control unit connector A (20P) and body ground.
Is there continuity?
YES - Repair short to ground in the wire between the door multiplex control unit connector and body ground.
NO - Go to step 6.
6. Check for continuity between the B9 terminal of passenger's multiplex control unit connector B (22P) and body ground.
Is there continuity?
YES - Repair short to ground in the wire between the passenger's multiplex control unit connector and the driver's multiplex control unit connector.
NO - Replace the driver's multiplex control unit and recheck the symptom.