Operation CHARM: Car repair manuals for everyone.

MICU Input Test




MICU Input Test

1. Turn the ignition switch to LOCK (0).

2. Remove the fuse lid panel, and remove the driver's dashboard lower cover.

3. Disconnect under-dash fuse/relay box connectors A, B, N, Q, R, and Y.

NOTE: All connector views are wire side of female terminals.






4. Inspect the connector and socket terminals to make 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 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 under-dash fuse/relay box, 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. If multiple failures are found on more than one control unit, replace the under-dash fuse/relay box (includes the MICU).

- USA models Under-Dash Fuse/Relay Box Removal and Installation (USA Models)
- Canada models Under-Dash Fuse/Relay Box Removal and Installation (Canada Models)

If input failures are related to a particular control unit, replace the control unit.