Test No. 25: Power Door Locks May Not Be Locked Or Unlocked When Using Power Door Lock Control Switch
- 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 power door lock operation.
- Check wiring harness and electrical connectors between power door lock control switch and passenger's side Junction Block (J/B) Electronic Control Unit (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. Passenger's side J/B ECU is located at passenger'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 as necessary and recheck power door lock operation.
- Check passenger's side J/B ECU for proper voltage and input signals. See PASSENGER'S SIDE JUNCTION BLOCK 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 power door lock operation.
- Replace passenger's side J/B ECU with a known-good passenger's side J/B ECU and recheck power door lock operation. If power door locks operate properly, original passenger's side J/B ECU was defective. If power door locks still do not operate properly, check wiring harness and electrical connectors for passenger's side J/B ECU 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.