Circuit/System Description
WARNING: This page is about a different car, the 2009 Pontiac Torrent and 2009 Chevrolet Equinox. However, it is still accessible from the selected car via links, so may be relevant.
The rear differential clutch control module (CCM) provides a power and ground switching circuits to the coil. The coil receives current from the CCM through PWM low side driver, and converts that signal into torque through the clutch to the rear tires when all wheel drive (AWD) is requested.