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Test No. 42: All Functions Of Wireless Door Lock Control System Do 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.
CAUTION: 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. Check multiplex control system for DTCs and proper operation. 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. Turn ignition off. Disconnect 25-pin body control ECU electrical harness connector B4 and 5-pin wireless door lock control receiver electrical harness connector. Check Green/Red wire between 25-pin body control ECU electrical harness connector B4 terminal No. 7 and 5-pin wireless door lock control receiver electrical harness connector terminal No. 3. See Figure. See POWER DOOR LOCKS in SYSTEM WIRING DIAGRAMS article. If wire, harnesses and connectors are okay, go to next step. If wire, harnesses or connectors are defective, repair as necessary. After repairs, perform confirmation test. See CONFIRMATION TEST .
  3. Turn ignition off. Replace wireless door lock control receiver with a known-good wireless door lock control receiver and recheck system operation. If system still does not operate properly, reinstall original wireless door lock control receiver and go to next step. If system operates properly, replace original wireless door lock control receiver. After repairs, perform confirmation test. See CONFIRMATION TEST .
  4. Check key unlock warning switch. See KEY UNLOCK WARNING SWITCH under COMPONENT TESTS under STEERING COLUMN SWITCHES - AVALON article in ACCESSORIES & EQUIPMENT. If key unlock warning switch is okay, go to next step. If key unlock warning switch is defective, replace key unlock warning switch. After repairs have been made, perform confirmation test. See CONFIRMATION TEST .
  5. Check key unlock warning switch reference circuit by checking Red/Yellow wire and electrical connectors between 2-pin key unlock warning switch terminal No. 2 and 25-pin body control ECU connector B4 terminal No. 17. See Figure. Key unlock warning switch may also be referred to as unlock switch. If wiring harness and electrical connectors are okay, go to next step. If wiring harness or electrical connectors are defective, repair as necessary. See POWER DOOR LOCKS in SYSTEM WIRING DIAGRAMS article. Note that Red/Yellow wire passes through junction block No. 4 located behind right kick panel. After repairs have been made, perform confirmation test. See CONFIRMATION TEST .
  6. Check key unlock warning switch ground circuit by checking White/Black wire and electrical connectors between 2-pin key unlock warning switch terminal No. 1 and wiring harness ground point located under left side of dash. If wiring harness and electrical connectors are okay, go to next step. If wiring harness or electrical connectors are defective, repair as necessary. See POWER DOOR LOCKS in SYSTEM WIRING DIAGRAMS article. Note that White/Black wire passes through junction block No. 3 located behind left kick panel. After repairs have been made, 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 .
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