Exterior Handle Switch: Operation
WARNING: This page is about a different car, the 2004 Chrysler Pacifica. However, it is still accessible from the selected car via links, so may be relevant.
When the exterior liftgate handle switch is depressed a hard-wired message is sent to the Body Control Module (BCM). The Body Control Module then sends a PCI data bus message to the power liftgate control module. The BCM message includes lock status and PRNDL position, which the power liftgate control module interprets. If operating conditions are met, the power liftgate control module then applies power to the latch mounted actuator, which moves the liftgate from the primary closed and latched position to the open and movable position.
If the liftgate is not pulled open within a few seconds, once the latch releases, the latch will automatically cinch closed.