Radio/HVAC Controls

WARNING: This page is about a different car, the 2012 Buick Regal. However, it is still accessible from the selected car via links, so may be relevant.

When equipped with the navigation radio, the radio controls communicate radio control inputs directly to the navigation radio with the CAN Graphical Interface (CGI) data circuits. After receiving the message the radio will perform the requested function. Messages communicated between the radio and the radio controls include the following:

Button presses/knob rotations
Commands for the state of indicators
Radio control back-lighting

The HVAC controls are a separate component from the radio controls. HVAC data for controls and status indicators is communicated between the HVAC controls and the HVAC control module with a separate LIN serial data circuit. HVAC status screen information from the HVAC control module is transmitted to the radio on the GMLAN serial data circuit. The radio then displays the desired screen information on the info display using the video data circuits.