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Multiplex Control Unit Input Test

MICU Input Test

1. Remove the left side kick panel.




2. Disconnect the under-dash fuse/relay box connectors D, E, H, J, K, N, P, X, and W.

NOTE: All connectors are wire side of female terminals.

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. With the connectors still disconnected from the under-hood fuse/relay box, make these input tests at the connector(s).
- 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 5.




5. Reconnect the connectors to the under-dash fuse/relay box, and make sure 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, the multiplex integrated control unit must be faulty, replace the under-dash fuse/relay box assembly.