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Multiplex Control Unit Input Test

Door Unit:
1. Carefully pry off the driver's door switch trim.
2. Disconnect the connectors (A).




3. Inspect the connector and socket terminals to be sure they are all making good contact.
- If the terminals are bent, loose or corroded, repair them as necessary, and recheck the system,.
- If the terminals look OK, go to step 4.




4. Make the following input tests at 20P connector A.
- If any test indicates a problem, find and correct the cause, then recheck the system.
- If all the input tests prove OK, go to step 5.

Passenger's Unit
5. Remove the passenger's multiplex control unit from the passenger's under-dash fuse/relay box.




6. Inspect the connector and socket terminals to be sure they are all making good contact.
- If the terminals are bent, loose or corroded, repair them as necessary, and recheck the system.
- If the terminals look OK, go to step 7.




7. Make the following input tests at 22P connector B and the passenger's under-dash fuse/relay box socket.
- If any test indicates a problem, find and correct the cause, then recheck the system.
- If all the input tests prove OK, go to step 8.

Driver's Unit:
8. Remove the driver's multiplex control unit from the driver's under-dash fuse/relay box.




9. Inspect the connector and socket terminals to be sure they are all making good contact.
- If the terminals are bent, loose or corroded, repair them as necessary, and recheck the system.
- If the terminals look OK, go to step 10.




10. Make the following input tests at 22P connector B and the driver's under-dash fuse/relay box socket.
- If any test indicates a problem, find and correct the cause, then recheck the system.
- If all the input tests prove OK, troubleshoot the Multiplex Control System.