Diagnostic Aids

WARNING: This page is about a different car, the 2018 GMC Terrain and 2018 Chevrolet Equinox. However, it is still accessible from the selected car via links, so may be relevant.

Whenever the liftgate control module loses power or is disconnected, the ignition must be cycled OFF then ON in order to reactivate the liftgate control module.
If the liftgate mode switch is in the Off position, the liftgate will only open and close manually. Before testing the liftgate for power open and power close functions, verify that the liftgate mode switch is in the 3/4 or MAX position.