Door lock actuators are electrically controlled components that allow for locking and unlocking the doors on vehicles that feature a power door locking system. A car door lock actuator is quite a simple part that controls the door latch mechanism by means of spur gears actuated by an electric motor. The last gear turns the rack attached to the actuator rod. This way, the rotational force of the motor turns into the linear motion that operates the door lock. When a power door lock actuator or some of its components fail, the mechanism can operate erratically or may not function at all, causing major inconveniences. Before it stops working, a faulty actuator can produce unusual noises like squeaking or buzzing, which may indicate a malfunctioning motor or gears. FAERSI Door Lock Actuator is made with high-quality plastic and identical in fit, form and function to the original, realizing direct replacement & easy to install features. A door lock actuator is limited to only one door so please check the position before purchasing.