Test No. 27: Key Confinement Prevention Function Does Not Operate

NOTE: Key confinement prevention function prevents the doors from being locked if ignition key is in the ignition lock cylinder.

Check door unlock detection switch on driver's side front door and passenger's side front door. See DOOR UNLOCK DETECTION SWITCH under COMPONENT TESTS. If door unlock detection switches are okay, go to next step. If any door unlock detection switch is defective, replace door unlock detection switch and recheck operation of key confinement prevention function.
Check wiring harness and electrical connectors between each door unlock detection switch and body Electronic Control Unit (ECU). See WIRING DIAGRAMS in POWER DOOR LOCKS - TRUCKS (EXCEPT SEQUOIA) article. Door unlock detection switch may also be referred to as unlock detection switch. Body ECU is located at driver's side of instrument panel. See Figure. If wiring harness and electrical connectors are okay, go to next step. If wiring harness or electrical connector are defective, repair wiring harness or electrical connector as necessary and recheck operation of key confinement prevention function.
Check that door courtesy switch for each door is mounted securely in pillar post to provide good ground connection. Door courtesy switches are located on pillar post at front of each door. See Figure. If door courtesy switch is tight and good ground connection exists, go to next step. If door courtesy switch is loose, tighten door courtesy switch and recheck operation of key confinement prevention function. If key confinement prevention function still does not operate, go to next step. If key confinement prevention function operates, the problem was the loose door courtesy switch.
Check door courtesy switch for each door. See DOOR COURTESY SWITCH under COMPONENT TESTS. If door courtesy switch is okay, go to next step. If door courtesy switch is defective, replace door courtesy switch and recheck operation of key confinement prevention function.
Check wiring harness and electrical connectors between door courtesy switch and body ECU. See WIRING DIAGRAMS in POWER DOOR LOCKS - TRUCKS (EXCEPT SEQUOIA) article. If wiring harness and electrical connectors are okay, go to next step. If wiring harness or electrical connector are defective, repair as necessary and recheck operation of key confinement prevention function.
Check power door lock control switch. See POWER DOOR LOCK CONTROL SWITCH under COMPONENT TESTS. If power door lock control switch is okay, go to next step. If power door lock control switch is defective, replace switch and recheck operation of key confinement prevention function.
Check wiring harness and electrical connectors between power door lock control switches and body ECU. See WIRING DIAGRAMS in POWER DOOR LOCKS - TRUCKS (EXCEPT SEQUOIA) article. Power door lock control switch may also be referred to as door lock control switch. If wiring harness and electrical connectors are okay, go to next step. If wiring harness or electrical connector are defective, repair as necessary and recheck operation of key confinement prevention function.
Check body ECU for proper voltage and input signals. See BODY ELECTRONIC CONTROL UNIT under PIN VOLTAGE TESTS. If proper voltage and input signals exist, go to next step. If proper voltage and input signals do not exist, repair as necessary and recheck operation of key confinement prevention function.
Replace body ECU with a known-good body ECU and recheck operation of key confinement prevention function. If key confinement prevention function operates properly, original body ECU was defective. If key confinement prevention function still does not operate properly, check wiring harness and electrical connectors for body ECU, door unlock detection switch, door courtesy switch and power door lock control switch for intermittent problem. See WIRING DIAGRAMS in POWER DOOR LOCKS - TRUCKS (EXCEPT SEQUOIA) article. Repair wiring harness or electrical connector as necessary.