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Multiplex Control Unit Input Test

Multiplex Control Unit Input Test

1. Remove the driver's dashboard lower cover.




2. Unbolt the under-dash fuse/relay box and pull it down.

NOTE: All connectors are wire side of female terminals.

3. Disconnect the connectors.
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.







5. Reconnect the connectors, turn the ignition switch ON (II) to wake-up the system, and make these input tests at the appropriate connectors.
- If any test indicates a problem, find and correct the cause, then recheck the system.
- If all the input tests prove OK, the multiplex control unit must be faulty, replace the under-dash fuse/relay box assembly.