GM Genuine Parts HVAC Control Panels, or control heads, are designed, engineered, and tested to rigorous standards, and are backed by General Motors. These control heads translate the users commands into mechanical, vacuum, or electrical signals to operate the blower fan and the blend, mode, and recirculation doors. Some systems with automatic functions have an integrated or remotely mounted computer module that monitors the control head inputs and the cabin and duct temperatures to adjust the blower speed and door positions to maintain the desired cabin temperature. GM Genuine Parts are the true OE parts installed during the production of or validated by General Motors for GM vehicles. Some GM Genuine Parts may have formerly appeared as ACDelco GM Original Equipment (OE).