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Test No. 43: Lock Or Unlock Function 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: Wireless door lock control receiver is monitored by the body control ECU and will set a DTC. See MULTIPLEX CONTROL SYSTEMS - AVALON under COMMUNICATION DEVICES in ACCESSORIES & EQUIPMENT before servicing wireless door lock control system.
NOTE: Wireless door lock control system may also be referred to as remote keyless entry system.
  1. If multiplex control system is operating properly and no DTCs exist, go to next step. If multiplex control system is operating properly and DTCs exist, perform service procedure to repair fault. See MULTIPLEX CONTROL SYSTEMS - AVALON under COMMUNICATION DEVICES in ACCESSORIES & EQUIPMENT. After repairs, perform confirmation test. See CONFIRMATION TEST .
  2. Check suspect door key lock and unlock switch on driver door or front passenger door. See DOOR KEY LOCK & UNLOCK SWITCH under COMPONENT TESTS under POWER DOOR LOCKS WITHOUT KEYLESS ENTRY - AVALON article under DOOR LOCKS & ANTI-THEFT SYSTEMS in ACCESSORIES & EQUIPMENT. If door key lock and unlock switch is okay, go to next step. If door key lock and unlock switch is defective, replace door key lock and unlock switch. After repairs, perform confirmation test. See CONFIRMATION TEST .
  3. Turn ignition off. If suspect lock is located on driver door, disconnect 25-pin driver door ECU electrical harness connector and Black 6-pin driver side power door lock electrical harness connector. If suspect lock is located on front passenger door, disconnect 20-pin front passenger door ECU electrical harness connector and Black 6-pin front passenger side power door lock electrical harness connector. See Figure. Check wires between responsible door ECU and corresponding door key lock and unlock switch. See POWER DOOR LOCKS in SYSTEM WIRING DIAGRAMS article.
    • On driver door, check Blue wire between 25-pin driver door ECU electrical harness connector terminal No. 10 and Black 6-pin driver side power door lock electrical harness connector terminal No. 6. Check Blue/White wire between 25-pin driver door ECU electrical harness connector terminal No. 22 and Black 6-pin driver side power door lock electrical harness connector terminal No. 5.
    • On front passenger door, check Blue/Yellow wire between 20-pin front passenger door ECU electrical harness connector terminal No. 2 and Black 6-pin front passenger side power door lock electrical harness connector terminal No. 1. Check Blue/White wire between 20-pin front passenger door ECU electrical harness connector terminal No. 3 and Black 6-pin front passenger side power door lock electrical harness connector terminal No. 2.
    If wires, harnesses and connectors are okay, go to next step. If wires, harnesses or connectors are defective, repair as necessary. After repairs, perform confirmation test. See CONFIRMATION TEST .
  4. Check wire, harnesses and connectors between door unlock detection switches and responsible door ECU. See POWER DOOR LOCKS in SYSTEM WIRING DIAGRAMS article.
    • For driver door unlock detection switch, check Light Green wire between driver door ECU 25-pin electrical harness connector terminal No. 24 and Black driver door lock assembly 6-pin electrical harness connector terminal No. 4. See Figure.
    • For front passenger door unlock detection switch, check Yellow wire between front passenger door ECU 20-pin electrical harness connector terminal No. 4 and Black front passenger door lock assembly 6-pin electrical harness connector terminal No. 4. See Figure.
    If wires, harnesses and connectors are okay, go to next step. Repair any defective wire, harness or connector as required. See POWER DOOR LOCKS in SYSTEM WIRING DIAGRAMS article. After repairs have been made, perform confirmation test. See CONFIRMATION TEST .
  5. 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 .
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