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.
Ignition voltage is supplied to the sunroof control module by the BCM. B+ is applied to the sunroof control module via the S/ROOF fuse. The sunroof control module supplies each of the switch signal circuits with a 12-volt reference. When a switch is pressed the signal circuit is pulled low signaling the sunroof open or close request. The sunroof control module determines the motor direction based on inputs received from the sunroof switch. When the module reverses the polarity of the applied voltage, the motor reverses direction.