Circuit/System Verification
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.
Ignition ON, command the rear windows UP and DOWN by using the window switches on the driver master control and their respective rear window switches. The rear windows should perform the UP and DOWN function from each switch.