Test No. 15: Light Failure Warning Light Does Not Light Up

NOTE: The multiplex communication system monitors various light system components. Ensure multiplex communication system is operating properly. See MULTIPLEX CONTROL SYSTEMS - AVALON article under COMMUNICATION DEVICES in ACCESSORIES & EQUIPMENT. If the multiplex communication system is functioning properly and no diagnostic trouble codes are stored, the body control system must be interrogated next. The body control system monitors the light failure sensor and turns on the warning light. See BODY CONTROL SYSTEMS - AVALON article under COMMUNICATION DEVICES in ACCESSORIES & EQUIPMENT for complete diagnosis of taillight system.