Operation CHARM: Car repair manuals for everyone.

Communication Line Test

Communication Line Test

BRN Wire Communication Line Test


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




4. Check for continuity between No.2 terminal of the driver's under-dash fuse/relay box socket and No.15 terminal of the door multiplex control unit connector A (20P).

Is there continuity?

YES - Replace the multiplex control unit most closely related to failure.

NO - Repair an open in the wire between the door multiplex connector and the driver's under-dash fuse/relay box If the wire is OK replace the under dash fuse/relay box.

PNK Wire Communication Line Test

1. Disconnect driver's multiplex control unit connector B (22P).
2. Disconnect passenger's multiplex control unit connector B (22P).




3. Check for continuity between No.1 terminal of the driver's multiplex connector B (22P) and No.9 terminal of the passenger's multiplex connector B (22P).

Is there continuity?

YES - Replace the multiplex control unit most closely related to the failure.

NO - Repair an open in the wire between the door multiplex B (22P) connector and the passenger's multiplex B (22P) connector.

Shorted Communication Line Test

1. 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 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 No.9 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.