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Test No. 73: Driver Door Two-Operation 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: Two-operation unlock function unlocks all doors when using key in external door lock cylinder. Turning key once in driver door lock unlocks driver door only. Turning key twice in succession in driver door lock unlocks all doors. Turning key once in front passenger door lock unlocks all doors. There is no function of turning key twice in front passenger door lock.
NOTE: Door key lock and unlock switch 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.
  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 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. Disconnect 20-pin front passenger door ECU electrical harness connector and Black 6-pin front passenger power door lock electrical harness connector. See Figure. 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. See POWER DOOR LOCKS in SYSTEM WIRING DIAGRAMS article. 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 the following fuses located in driver side junction block: ECU-B (7.5-amp) and ECU-IG NO. 2 (10-amp) and FR P/W (20-amp). Check the following fuse located in engine compartment junction block: DCC (30-amp). See Figure. If fuses are okay, go to next step. If any fuse is defective, repair wiring for appropriate fuse. See POWER DISTRIBUTION and POWER DOOR LOCKS in SYSTEM WIRING DIAGRAMS article. After repairs, perform confirmation test. See CONFIRMATION TEST .
  5. Turn ignition off. Remove front passenger door ECU from front passenger door. Disconnect front passenger door ECU 20-pin electrical harness connector. Using DVOM, check voltage between ground circuit at front passenger door ECU 20-pin electrical harness connector terminal No. 8 (White/Black wire) and power circuits at terminal No. 12 (White/Green wire) and terminal No. 20 (Blue/Black wire). Blue/Black wire changes to a Blue wire at right front door-to-instrument panel harness connection located behind right kick panel. Voltage should be 10-14 volts. If all voltage readings are within specification, go to next step. If either voltage reading is not within specification, repair power feed circuit from battery. See POWER DISTRIBUTION in SYSTEM WIRING DIAGRAMS article. After repairs, perform confirmation test. See CONFIRMATION TEST .
  6. With ignition off and front passenger door ECU 20-pin electrical harness connector disconnected, check for opens and shorts in wiring harnesses and electrical connectors between battery and front passenger door ECU and between body ground points at left and right kick panels and front passenger door ECU. See POWER DISTRIBUTION and GROUND DISTRIBUTION in SYSTEM WIRING DIAGRAMS article. If wiring harnesses and electrical connectors are okay, go to next step. If wiring harnesses or electrical connectors are defective, repair as necessary. After repairs, perform confirmation test. See CONFIRMATION TEST .
  7. Substitute original front passenger door ECU with a known-good unit and recheck power window system operation. If power door lock operates properly, original front passenger door ECU was defective. If power door lock still does not operate properly, perform front passenger door ECU pin voltage check. See FRONT PASSENGER DOOR 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 front passenger door ECU. After repairs, perform confirmation test. See CONFIRMATION TEST . If power door lock still does not operate properly, go to next step.
  8. 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.
  9. Check wiring harness and electrical connectors between battery and body control ECU, between battery and driver side junction block, between battery and engine compartment junction block, between driver side junction block and driver door ECU, between driver side junction block and front passenger door ECU, between engine compartment junction block and body control ECU, between body control ECU and driver door ECU, between body control ECU and front passenger door ECU, and all power and ground connections. See POWER DOOR LOCKS in SYSTEM WIRING DIAGRAMS article. If wiring harnesses or electrical connectors are defective, repair as necessary. After repairs, perform confirmation test. See CONFIRMATION TEST .
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