Radio/HVAC Controls

WARNING: This page is about a different car, the 2011 Chevrolet Volt. However, it is still accessible from the selected car via links, so may be relevant.

The radio/HVAC controls are a separate component from the radio. The control assembly contains control knobs, switches, buttons and touch controls for all radio and HVAC functions, configuration and personalization, and other vehicle systems. Refer to the Owners Manual for additional information.

The control assembly communicates radio control inputs directly to the 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/HVAC controls include the following:

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

HVAC data for controls and status indicators is communicated between the control assembly 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.