Multiplex Control Unit Input Test

Remove the dashboard lower cover DRIVER'S DASHBOARD LOWER COVER REMOVAL/INSTALLATION ).
Disconnect the under-dash fuse/relay box connectors C, E, F, J, K, 0, P, Q, X and Y.
NOTE: All connectors are wire side of female terminals.

Fig 1: Identifying Under-Dash Fuse/Relay Box Connectors
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.
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 all the input tests prove OK, go to step 5.
Fig 2: Multiplex Control Unit Input Test (Connectors Disconnected)
Reconnect the connectors to the under-dash fuse/relay box, and make sure these input tests at the appropriate connectors on the underdash 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 control unit must be faulty, replace the under-dash fuse/relay box assembly.
Fig 3: Multiplex Control Unit Input Test (Connectors Connected - 1 Of 2)

Fig 4: Multiplex Control Unit Input Test (Connectors Connected - 2 Of 2)