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, observe the scan tool BCM SWC Bank 1 Status parameter. The reading should be idle and change between SW1-SW7 when pushing the appropriate switch.