Driver's Multiplex Control Unit
Turn ignition switch to OFF position. Remove under-dash fuse/relay box located under instrument panel. See UNDER-DASH FUSE/RELAY BOX under REMOVAL & INSTALLATION. Disconnect driver's multiplex control unit from under-dash fuse/relay box. Inspect connectors and terminals. Check for bent, loose or corroded terminals. Repair connector terminals as necessary and retest system. Perform passenger's multiplex control unit input tests. See Fig 1 . If driver's multiplex control unit input tests are okay, replace faulty control unit.