In an automotive context, a rear door actuator is a component that is used to lock and unlock a rear liftgate, hatchback, or other similar door. This term can also refer to actuators found in rear side doors, though those are more commonly called left rear or right rear door actuators. The purpose of a rear door actuator is to open or close a locking mechanism, either allowing the door to be opened or securing it shut. These components can be either manual or powered, though some include both options. Powered actuators are often remote controlled, and sometimes also include an exterior key tumbler or interior button as an alternative means of activation.
The two main types of door lock actuators are manual and powered. A manual rear door actuator is little more than a button or switch that is mechanically connected to the lock by one or more rods and pivots. When the button or switch is pressed, the motion of the rod or rods can cause the lock to activate. This can then be reversed by pushing the other side of the switch or pulling up on the button, depending on the particular design. Manual rear door actuators can typically also be operated by turning a key in an exterior tumbler.
Powered door lock actuators are typically a little more complicated, and some of them even include manual components as well. This type of rear door actuator may be operated by a keyless entry device or a main door control panel that is typically located somewhere near the driver's seat. These actuators sometimes also include an electric or manual switch on the rear door. Unlike manual door lock actuators, these devices typically consist of a small motor that is connected to a short rod. When the motor is activated by a switch or wireless signal, it pushes the rod out or pulls it in, which in turn activates the locking mechanism within the door.
In most cases, rear door actuators are located behind removable door panels. Before these units can be replaced, the door usually needs to be opened so that the panel can be pulled back or removed. In some cases, it is also possible to pull the panel back without opening the door, which can provide access to the locking mechanism if the rear door actuator has broken. The door may then be unlocked and opened so that a new unit can be installed.