Power Door Lock Actuator: Testing and Inspection

Before you proceed with this diagnosis, confirm proper power lock switch, power lock and Remote Keyless Entry (RKE) module or Central Timer Module (CTM), and power lock switch output circuit operation. See Power Lock Switch, and Power Lock and Remote Keyless Entry Module or Central Timer Module in the Diagnosis. Remember, the module circuitry controls the output to each of the power lock motors.
1. Check each power lock motor for correct operation while moving the power lock switch to both the Lock and Unlock positions. If all of the power lock motors are inoperative, go to Step 3. If one power lock motor is inoperative, go to Step 4.
2. If all of the power lock motors are inoperative, the problem may be caused by one shorted motor. Unplugging a shorted power lock motor from the power lock circuit will allow the good power lock motors to operate. Unplug each power lock motor wire harness connector, one at a time, and recheck both the lock and unlock functions by operating the power lock switch. If all of the power lock motors are still inoperative after the above test, check for a short or open circuit between the power lock motors and the power lock and RKE module or the CTM. If unplugging one power lock motor causes the other motor to become functional, go to Step 4 to test the unplugged motor.
3. Once it is determined which power lock motor is inoperative, that motor can be tested as follows. Unplug the wire harness connector at the inoperative power lock motor. Apply 12 volts to the motor terminals to check its operation in one direction. Reverse the polarity to check the operation in the other direction. If OK, repair the short or open circuits between the power lock motor and the power lock and RKE module or the CTM as required. If not OK, replace the faulty power lock motor.