Test No. 38: Lock Or Unlock Function Does Not Operate
- Check multiplex control system to see if Diagnostic Trouble Code (DTC) B1222 (Toyota hand-held tester) or DTC No. 22 (DOOR open indicator light) exists when operating door key lock and unlock switch on driver's side front door by using ignition key to lock and unlock the door lock assembly. Check that DTC B1224 (Toyota hand-held tester) or DTC No. 24 (DOOR open indicator light) exists when operating door key lock and unlock switch on passenger's side front door by using ignition key to lock and unlock the door lock assembly. See MULTIPLEX CONTROL SYSTEMS - AVALON article. If these DTCs are not output when operating appropriate door key lock and unlock switch, contacts are defective in the door key lock and unlock switch. If these DTCs are output when door key lock and unlock switch is not being operated, this indicates door key lock and unlock switch is stuck. If these DTCs are not output when operating each door key lock and unlock switch or DTCs exist when not operating appropriate door key lock and unlock switch, go to next step. If these DTCs are output when operating each door key lock and unlock switch, go to step 4.
- Check appropriate door key lock and unlock switch on driver's side front door or passenger's side front door. See DOOR KEY LOCK & UNLOCK SWITCH under COMPONENT TESTS. 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 and recheck keyless entry system operation.
- Check wiring harness and electrical connectors between door key lock and unlock switch on driver's side front door and driver's door Electronic Control Unit (ECU), and between door key lock and unlock switch on passenger's side front door and passenger's door ECU. See WIRING DIAGRAMS in KEYLESS ENTRY SYSTEMS - AVALON article. Driver's door ECU and passenger's door ECU are located on the door and is incorporated into the power window switch assembly. See Figure. If wiring harness and electrical connector are okay, go to next step. If wiring harness or electrical connector are defective, repair as necessary and recheck keyless entry system operation.
- 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 lock assembly and recheck keyless entry system operation.
- Check wiring harness and electrical connectors between door unlock detection switch on driver's side front door and driver's door ECU, and between door unlock detection switch on passenger's side front door passenger's door ECU. See WIRING DIAGRAMS in KEYLESS ENTRY SYSTEMS - AVALON article. Driver's door ECU and passenger's door ECU are located on each door and is incorporated into the power window switch assembly. 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 keyless entry system operation.
- 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 keyless entry system operation.
- Replace body ECU with a known-good body ECU and recheck keyless entry system operation. If keyless entry system operates properly, original body ECU was defective. If keyless entry system still does not operate properly, check wiring harness and electrical connectors for body ECU and keyless entry system for an intermittent problem. Repair wiring harness or electrical connector as necessary.