Heated/Cooled Seat Switches

WARNING: This page is about a different car, the 2009 GMC Sierra, 2009 GMC Cab & Chassis Sierra, 2009 Chevrolet Silverado, and 2009 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.

The heated and cooled seat system is controlled through the heated and cooled seat switches that are located on the door panels. When either the heat or cool seat switch is pressed, ground is applied through the switch contacts and the switch signal circuit to the door lock/window switch. In response to this signal, the door lock/window switch sends a serial data message to the memory seat module (MSM) indicating the switch input. In response to this message, the MSM then sends a pulse width modulation (PWM) signal through the heated/cool seat mode signal circuit to the CCSM indicating the heated or cooled seat request. The door lock/window switch then applies a ground through the appropriate heat or cool seat indicator control circuit to the switch illuminating the selected heat or cool mode indicator. At the same time, the door lock/window switch also applies a ground through the appropriate high, medium, or low temperature indicator control circuits illuminating temperature mode indicators.