Test No. 9: Lock Or Unlock Function Does Not Operate
- Check door key lock and unlock switch for 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 switch and recheck keyless entry system operation.
- Check wiring harness and electrical connectors for Green and Blue/Black wires between door key lock and unlock switch on passenger's side front door and body Electronic Control Unit (ECU). See WIRING DIAGRAMS in POWER DOOR LOCKS & REMOTE KEYLESS ENTRY SYSTEMS - PRIUS article. Body ECU is located at driver's side of instrument panel on the fuse/relay box and contains an 18-pin and 20-pin electrical connector. 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 keyless entry system operation.
- Check door unlock detection switches on passenger's side front door and both rear passenger's doors. 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 keyless entry system operation.
- Check wiring harness and electrical connectors between door unlock detection switch on passenger's side front door and both rear passenger's doors and body ECU. See WIRING DIAGRAMS in POWER DOOR LOCKS & REMOTE KEYLESS ENTRY SYSTEMS - PRIUS article. 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 and input signals do 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 between body ECU, door key lock and unlock switch on passenger's side front door, and door unlock detection switches on passenger's side front door and both rear passenger's doors for intermittent problem. See WIRING DIAGRAMS in POWER DOOR LOCKS & REMOTE KEYLESS ENTRY SYSTEMS - PRIUS article. Repair wiring harness or electrical connector as necessary.