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Component Tests and General Diagnostics

Control Unit Input Test

1. Before testing, troubleshoot the multiplex integrated control system using B-CAN System Diagnosis Test Mode A.

Multiplex Integrated Control Unit

2. Turn the ignition switch OFF.
3. Remove the left kick panel.




4. Disconnect the driver's under-dash fuse/relay box connectors.

NOTE: All connectors are wire side of female terminals.

5. 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 are OK, go to step 6.




6. With the connectors still disconnected, make these input tests at the connectors.
- 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. Reconnect the connectors to the driver's under-dash fuse/relay box, and make these input tests at the connectors.
- 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.

8. Turn the ignition switch OFF.
9. Remove the gauge control module.




10. Disconnect the gauge control module connectors A (20P) and B (28P).
11. 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 12.




12. Reconnect the connectors to the gauge control module, and make these input tests at the connectors.
- 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 13.

13. Do the gauge self-diagnostic procedure.
- If the beeper sounds and the seat belt reminder light flashes, go to step 14.
- If the beeper does not sound or the seat belt reminder light does not flash, replace the gauge control module.

14. Substitute a known-good gauge control module, and recheck the system.
- If the symptom is gone, the gauge control module is faulty; replace it.
- If the symptom is still present, the multiplex integrated control unit (MICU) is faulty; replace the under-dash fuse/relay box.