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Control Unit Input Test

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 under-dash fuse/relay box connectors F, H and P.
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. Reconnect the connectors. Turn the ignition switch ON (II) and 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 7.

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




9. Disconnect the gauge control module connectors A and B.

NOTE: All connectors are wire side of female terminals.

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 are OK, go to step 11.




11. 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 the input tests prove OK, go to step 12.

12. Reconnect the connectors at the under-dash fuse/relay box and the gauge control module.
13. Perform the Gauge Self-diagnosis 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-hood fuse/relay box.