Circuit/System Description
WARNING: This page is about a different car, the 2016 GMC Acadia, 2016 Chevrolet Traverse, and 2016 Buick Enclave. However, it is still accessible from the selected car via links, so may be relevant.
The exterior liftgate control switch is an input to the body control module (BCM). The BCM supplies a signal to the exterior liftgate control switch and when the switch is pressed, signal circuit voltage goes low. When the BCM receives a liftgate release signal, the BCM will supply voltage and ground to the L/GATE relay coil, energizing the relay. When the relay is energized, battery voltage flows through the closed contacts of the relay to the liftgate latch assembly which activates allowing for the liftgate to be raised to the open position.