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Instrument Panel Control Module: Testing and Inspection

Control Unit Input Test

1. Before testing, trouble shoot the multiplex control system.
2. Remove the driver's multiplex control unit from the driver's under-dash fuse/relay box.




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. With the driver's multiplex control unit still disconnected, make these input tests at the connector and driver's under-dash fuse/relay box sockets.

- 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.




5. Reconnect the driver's multiplex control unit to the driver's under-dash fuse/relay box, and perform the given input tests at the appropriate connectors on the back of the driver's under-dash fuse/relay box. For driver's under-dash fuse/relay box connector socket location.

- If any test indicates a problem, find and correct the cause, then recheck the system.
- If all the input tests prove OK, the driver's multiplex control unit must be faulty, replace it.