Test No. 32: Two-Operation Unlock Function Does Not Operate
NOTE:
Two-operation unlock function unlocks all doors. When using the key and turning driver's side door lock once will unlock only driver's door. Turning driver's side door lock twice in succession will unlock all the doors
- 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 two-operation unlock function. See KEY UNLOCK WARNING SWITCH under REMOVAL & INSTALLATION.
- Check key unlock warning switch circuit by checking Red/Yellow wire and electrical connectors between terminal No. 2 at key unlock warning switch and terminal No. 17 at electrical connector B4 at body Electronic Control Unit (ECU). See WIRING DIAGRAMS in KEYLESS ENTRY SYSTEMS - AVALON article. Key unlock warning switch may also be referred to as unlock switch. Body ECU is located at driver's side of instrument panel on the fuse/relay box. See Figure. Electrical connector B4 (25-pin) and electrical connector B5 (25-pin) are located at each side of body ECU and a 12-pin electrical connector at rear of body ECU. See Figure. For electrical connector B4 location and 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 two-operation unlock 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 or input signal does not exist, repair as necessary and recheck operation of two-operation unlock function.
- Replace body ECU with a known-good body ECU and recheck operation of two-operation unlock function. If two-operation unlock function system operates properly, original body ECU was defective. If two-operation unlock function system still does not operate properly, check wiring harness and electrical connectors for body ECU and key unlock warning switch circuit for an intermittent problem. See WIRING DIAGRAMS in KEYLESS ENTRY SYSTEMS - AVALON article. Repair wiring harness or electrical connector as necessary.