Test No. 3: 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.
- If Toyota hand-held tester is available, go to next step. If Toyota hand-held tester is not available, go to step 3.
- Connect hand-held tester to Data Link Connector (DLC) No. 3. See Fig 1. Using hand-held tester manufacturer's instructions, check operation of key unlock warning switch while using the DATA LIST. Key unlock warning switch should be on when ignition key is in ignition lock cylinder and should be off when ignition key is removed from ignition lock cylinder. If key unlock warning switch does not operate properly, remove hand-held tester. Go to next step. If key unlock warning switch operates properly, remove hand-held tester. Go to step 5.
- Check key unlock warning switch. See KEY UNLOCK WARNING SWITCH under COMPONENT TESTS. If key unlock warning switch is okay, go to next step. If key unlock warning switch is defective, replace key unlock warning switch and recheck operation of key confinement prevention function. See KEY UNLOCK WARNING SWITCH under REMOVAL & INSTALLATION.
- Check key unlock warning switch circuit by checking Yellow/Green wire and electrical connectors between terminal No. 2 at key unlock warning switch and terminal No. 22 at body Electronic Control Unit (ECU) electrical connector B7. See WIRING DIAGRAMS in POWER DOOR LOCKS & REMOTE KEYLESS ENTRY SYSTEMS - SEQUOIA article. Key unlock warning switch may also be referred to as unlock switch. Body ECU is located behind driver's side of instrument panel and contains 3 electrical connectors. See Figure. For body ECU electrical connector terminal identification, see Figure. If wiring harness and electrical connectors are okay, go to next step. If wiring harness or electrical connector is defective, repair as necessary and recheck operation of key confinement prevention function.
- Check body Electronic Control Unit (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 and key unlock warning switch for intermittent problem. See WIRING DIAGRAMS in POWER DOOR LOCKS & REMOTE KEYLESS ENTRY SYSTEMS - SEQUOIA article. Repair wiring harness or electrical connector as necessary.