Door Lock Actuator
An electronic motor and gear assembly inside the door that locking and unlocking mechanisms are connected to, enabling power door locks.
A door lock actuator is a small, motorized component located inside each vehicle door. It is the actuator that makes power door locks possible. When the driver presses the door lock switch, uses the key fob, or when the vehicle automatically locks itself at speed, the body control module (BCM) sends an electrical pulse to the door lock actuator.
The actuator contains a tiny electric motor and a set of gears (often a worm gear) that convert the motor's high-speed rotation into the linear motion needed to push or pull the door latch linkages, locking or unlocking the door. It is typically integrated directly into the door latch assembly.
When a door lock actuator fails, it can prevent a door from locking or unlocking electrically, force the door to lock/unlock intermittently, or make a loud clicking or whining noise when activated. In a failed state, the door can usually still be locked or unlocked manually using the physical key or interior door lock knob, which is an important safety feature.