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Safety Indicator System Control Unit Input Test

Control Unit Input Test

1. Before testing, troubleshoot the multiplex control system.
2. Remove the driver's dashboard lower cover.
3. Disconnect the under-dash fuse/relay box connectors K, P, Q and Y.

NOTE: All connectors are shown from wire side of female terminals.






4. 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 5.

5. With the connectors still disconnected, make these input tests at the connector.
- 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 6.






6. Reconnect the connectors to the under-dash fuse/relay box, and make these input tests at the appropriate connectors on the 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, go to step 7.






7. Perform the Gauge Self-diagnostic Procedure. Initial Inspection and Diagnostic Overview
- If the safety indicator blinks, go to step 8.
- If the safety indicator does not blinks, replace the gauge control module.

8. Substitute a known-good under-dash fuse/relay box and recheck the system.
- If the symptom is gone, the multiplex control unit is faulty; replace the under-dash fuse/relay box.
- If the symptom is still present, the gauge control module must be faulty; replace the gauge control module.