Circuit/System Description
WARNING: This page is about a different car, the 2012 Buick Verano. However, it is still accessible from the selected car via links, so may be relevant.
The radio controls and information display are separate components from the radio. Each component is supplied battery voltage and ground. The radio uses the wake up circuit to control the power state of the display. The radio controls communicate with the info display module through the LIN serial data circuit. Display backlighting dimming level, graphical data, and radio control inputs are communicated over the CGI data circuits between the display and the radio.