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Control Unit Input Test

Lights-on, Key-in, Seat Belt Reminder, Key Light Timer, and Engine Oil Pressure Indicator Systems

Control Unit Input Test

1. Before testing these systems, troubleshoot the multiplex control system.

Driver's Multiplex Control Unit:

2. Remove the driver's 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. Make these input tests at the connector and 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, the control unit must be faulty; replace it.