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All Wireless Door Lock Control Functions Do Not Work

WARNING: This page is about a different car, the 2000 Toyota Avalon. However, it is still accessible from the selected car via links, so may be relevant.

  1. Retrieving DTCs

    Retrieve body control system DTCs. See RETRIEVING DIAGNOSTIC TROUBLE CODES under SELF-DIAGNOSTIC SYSTEMS in MULTIPLEX CONTROL SYSTEMS - AVALON article. If DTC 42 is indicated, go to DTC 42: WIRELESS DOOR LOCK RECEIVER MALFUNCTION under DIAGNOSTIC TESTS in MULTIPLEX CONTROL SYSTEMS - AVALON article. Repair as necessary and retest system. If DTC 42 is not indicated, go to next step.

  2. Checking Door Lock Receiver & Circuits

    Disconnect body control ECU connector B4 and wireless door lock receiver connector. See Figure and Figure . Using DVOM, check continuity on Blue/White wire between body control ECU harness connector terminal B4-21 and wireless door lock receiver harness connector. Check continuity on Green/Red wire between body control ECU harness connector terminal B4-7 and wireless door lock receiver harness connector. See WIRING DIAGRAMS . If either circuit does not have continuity, repair as necessary and retest system. If both circuits have continuity, go to next step.
  3. Replace wireless door lock receiver and retest system. If system still does not function correctly, reinstall original wireless door lock receiver and go to next step.

  4. Testing Key Unlock Warning Switch & Circuit

    Disconnect key unlock warning switch connector. See Figure. Using DVOM, check for continuity between switch connector terminals No. 1 (White/Black wire) and No. 2 (Red/Yellow wire). With key in ignition, continuity should be indicated. With key removed from ignition, continuity should not be indicated. If continuity is as specified, go to next step. If continuity is not as specified, replace key unlock warning switch.
  5. Check continuity in Red/Yellow wire between key unlock warning switch harness connector terminal No. 2 and body control ECU 25-pin connector B4, terminal No. 17. If continuity is not indicated, repair open in Red/Yellow wire as necessary and retest system. If continuity is indicated, go to next step.

  6. Testing Body Control ECU

    Check all voltage inputs to body control ECU. See BODY CONTROL ECU  under PIN VOLTAGE TESTS. If any voltage inputs are not as specified, repair affected circuit and retest system. See WIRING DIAGRAMS . If all voltage inputs are as specified, substitute known-good body control ECU and retest system. If system now works properly, replace body control ECU. If system still does not work, recheck all related system wiring and connections.
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