Control Unit Input Test

Control Unit Input Test

NOTE: If only the gauge lights do not work, check the gauge circuit and unit first ('04-05 models).

1. Before testing the dash lights brightness control functions, troubleshoot the multiplex control system.

Driver's Multiplex Control Unit

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 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 5.




5. Reconnect the driver's multiplex control unit to the driver's under-dash fuse/relay box, and perform the following input tests at the appropriate connectors on the driver's under-dash fuse/relay box.
- 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.