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Test No. 12: Automatic Headlights Off Delay System Does Not Operate

WARNING: This page is about a different car, the 2002 Toyota Avalon. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: Automatic light control system turns lights off after 30 seconds when all doors and luggage compartment (trunk) are closed with ignition in ACC or LOCK position with light control switch turned to position No. 2, or after 20 minutes or longer when a door or luggage compartment is open. Light control switch position No. 2 turns on headlights along with license plate lights, park lights, side marker lights, taillights and instrument panel lights. Lights will automatically turn off when driver door is opened with light control switch in position No. 1. Position No. 1 turns on park lights along with license plate lights, taillights, side marker lights and instrument panel lights. If doors are locked with wireless remote control transmitter, lights will turn off immediately.
  1. Open and close driver door. Ensure door courtesy light comes on when door is opened and goes off when door is closed. If courtesy light does not operate properly when door is opened and closed, check and replace courtesy light bulb as required. If bulb is okay, go to next step. If door courtesy light operates properly when driver door is opened and closed, go to step  5.
  2. Check driver door courtesy switch. See DOOR COURTESY SWITCH under COMPONENT TESTS under INSTRUMENT PANELS - AVALON article in ACCESSORIES & EQUIPMENT. If door courtesy switch is okay, go to next step. If door courtesy switch is defective, replace door courtesy switch. After repairs, perform confirmation test. See CONFIRMATION TEST .
  3. Check Red/Blue wire between body control ECU 25-pin connector B4 terminal No. 5 and driver door courtesy switch. See Figure. If wiring harness and electrical connectors are okay, go to next step. If wiring harness or electrical connectors are defective, repair as necessary. See INTERIOR LIGHTS in SYSTEM WIRING DIAGRAMS article. Note that Red/Blue wire of driver door courtesy switch passes through junction block No. 3 located behind left kick panel. After repairs have been made, perform confirmation test. See CONFIRMATION TEST .
  4. Check Red wire between driver door ECU 25-pin connector terminal No. 5 and Gray driver door courtesy light 2-pin connector terminal No. 1. Then check Red/Blue wire between driver door ECU 25-pin connector terminal No. 6 and Gray driver door courtesy light 2-pin connector terminal No. 2. If wiring harness and electrical connectors are okay, go to next step. If wiring harness or electrical connectors are defective, repair as necessary. See INTERIOR LIGHTS in SYSTEM WIRING DIAGRAMS article. After repairs have been made, perform confirmation test. See CONFIRMATION TEST .
  5. Check driver door control system. See DRIVER DOOR CONTROL SYSTEM  under TROUBLE SHOOTING. If no symptoms exist, go to next step. After symptoms are fixed, retest system and perform confirmation test. See CONFIRMATION TEST .
  6. Check multiplex control system. See MULTIPLEX CONTROL SYSTEMS - AVALON article under COMMUNICATION DEVICES in ACCESSORIES & EQUIPMENT. If no DTCs or symptoms exist, go to next step. If symptoms were fixed, retest system and perform confirmation test. See CONFIRMATION TEST .
  7. Check body control ECU ground circuits. See BODY COMPUTER in SYSTEM WIRING DIAGRAMS article. If ground circuits are faulty, repair and retest system. If ground circuits are okay, substitute original body control ECU with a known-good unit and recheck system operation. If system operates properly, original body control ECU was defective. If system still does not operate properly, perform body control ECU pin voltage check. See BODY CONTROL ELECTRONIC CONTROL UNIT  under PIN VOLTAGE TESTS. Check wiring harness and electrical connectors for an intermittent problem. Repair wiring harnesses or connectors as necessary. If voltage values, harnesses and connectors are okay, replace body control ECU. After repairs, perform confirmation test. See CONFIRMATION TEST . If symptom is still present, go to next step.
  8. Check wiring harness and electrical connectors for body ECU and key unlock warning switch for an intermittent problem. Repair wiring harnesses or connectors as necessary. After repairs, perform confirmation test. See CONFIRMATION TEST .
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