Component Tests and General Diagnostics

Control Unit Input Test

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

Multiplex Integrated Control Unit

1. Turn the ignition switch OFF.
2. Remove the left kick panel.
3. Disconnect the driver's under-dash fuse/relay box connectors.

NOTE: All connectors are 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 are OK, go to step 5.

5. 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 6.






6. 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 7.






Gauge Control Module

7. Turn the ignition switch OFF.
8. Remove the gauge control module.
9. Disconnect gauge control module connectors A (20P) and B (28P).






10. 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 11.

11. 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 12.






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

13. 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.