Control Unit Input Test

Before testing, troubleshoot the multiplex control system (see TROUBLESHOOTING ).
Remove the dashboard lower cover.
Disconnect the under-dash fuse/relay box connectors C, F, J, K, M, 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 5.
Reconnect the connectors, 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 6.
Fig 2: Control Unit Input Test (Connectors Connected)
Reconnect all connections 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 control unit must be faulty, replace the under-dash fuse/relay box assembly.
Fig 3: Control Unit Input Test (Under-Dash Fuse/Relay Box - Connectors Connected - 1 Of 2)

Fig 4: Control Unit Input Test (Under-Dash Fuse/Relay Box - Connectors Connected - 2 Of 2)