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Test No. 65: Key Confinement Prevention 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: Key confinement prevention function prevents doors from being locked if ignition key is in ignition lock cylinder.
  1. 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 .
  2. 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 .
  3. 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 .
  4. Open and close each door. Ensure door courtesy light comes on when each door is opened and goes off when each door is closed. If any door 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 each door is opened and closed, go to step  8.
  5. Check suspect door courtesy switch. See DOOR COURTESY SWITCH under COMPONENT TESTS in INSTRUMENT PANELS - AVALON article in ACCESSORIES & EQUIPMENT. If suspect door courtesy switch is okay, go to next step. If suspect door courtesy switch is defective, replace door courtesy switch. After repairs have been made, perform confirmation test. See CONFIRMATION TEST .
  6. Check wiring harness and electrical connectors between suspect door courtesy light switch and body control ECU. See INTERIOR LIGHTS in SYSTEM WIRING DIAGRAMS article.
    • Red/Blue wire between body control ECU 25-pin connector B4 terminal No. 5 and driver door courtesy light switch.
    • Orange wire between body control ECU 25-pin connector B5 terminal No. 3 and front passenger door courtesy light switch.
    • Red/White wire between body control ECU 25-pin connector B5 terminal No. 16 and each rear door courtesy light switch.
    If wiring harness and electrical connectors are okay for rear door courtesy light switches, go to step  8. If wiring harness and electrical connectors are okay for driver and front passenger door courtesy light switches, go to next step. If any 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 light switch passes through junction block No. 3 located behind left kick panel. Orange wire for front passenger door courtesy light switch and Red/White wires for rear door courtesy light switches pass through junction block No. 4 located behind right kick panel. After repairs have been made, perform confirmation test. See CONFIRMATION TEST .
  7. Check wiring harness and electrical connectors between suspect door courtesy light and appropriate door ECU. See INTERIOR LIGHTS in SYSTEM WIRING DIAGRAMS article.
    • For driver door courtesy light, 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.
    • For front passenger door courtesy light, check Red wire between front passenger door ECU 20-pin connector terminal No. 6 and Gray front passenger door courtesy light 2-pin connector terminal No. 1. Then check Red/Blue wire between front passenger door ECU 20-pin connector terminal No. 5 and Gray front passenger 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 .
  8. Check the following fuses located in driver side junction block: ECU-B (7.5-amp), ECU-IG NO. 2 (10-amp), GAUGE NO. 1 (10-amp) and DOOR NO. 1 (25-amp). Check the following fuses located in engine compartment junction block: DCC (30-amp) and DOOR NO. 2 (15-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 .
  9. Turn ignition off. Remove driver door ECU from driver door. See DRIVER DOOR OR FRONT PASSENGER DOOR ELECTRONIC CONTROL UNIT  under REMOVAL & INSTALLATION. See Figure. Turn ignition on. Using DVOM, backprobe between driver door ECU 25-pin electrical harness connector terminal No. 21 (Red/Black wire) and terminal No. 13 (White/Black wire). Voltage should be 10-14 volts. If voltage is 10-14 volts, go to next step. If voltage is not 10-14 volts, repair power feed circuit from battery. See POWER DISTRIBUTION in SYSTEM WIRING DIAGRAMS article. After repairs, perform confirmation test. See CONFIRMATION TEST .
  10. Turn ignition off. With driver door ECU removed from driver door, disconnect driver door ECU 25-pin electrical harness connector. Using DVOM, check voltage between ground circuit at driver door ECU 25-pin electrical harness connector terminal No. 13 (White/Black wire) and power circuits at terminal No. 23 (White/Green wire) and terminal No. 25 (Blue/Orange wire). 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 DOOR LOCKS in SYSTEM WIRING DIAGRAMS article. After repairs, perform confirmation test. See CONFIRMATION TEST .
  11. Check for opens and shorts in wiring harnesses and electrical connectors between battery and driver door ECU and between body ground points at left and right kick panels and driver 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 .
  12. Substitute original driver door ECU with a known-good unit and recheck manual switch operation of power door lock system. If key manual switch operation of power door lock system operates properly, original driver door ECU was defective. If manual switch operation of power door lock system still does not operate properly, perform driver door ECU pin voltage check. See DRIVER 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 driver door ECU. After repairs, perform confirmation test. See CONFIRMATION TEST . If manual switch operation of power door lock system still does not operate properly, go to next step.
  13. 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.
  14. 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 engine compartment junction block and body control ECU, and all power and ground connections. See POWER DOOR LOCKS in SYSTEM WIRING DIAGRAMS article. If wiring harnesses or 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 .
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