Function Control Knob

Function control knob can be placed in OFF, panel, panel/floor, floor, floor/defrost or defrost position. The function control knob operates a vacuum switch connected to appropriate actuator motors, which operate the floor/defrost and panel doors.

Outside/recirculation door is controlled by a vacuum valve and vacuum motor. When function control knob is in the OFF position, vacuum is applied to outside/recirculation door vacuum motor to shut off outside airflow. When function control knob is in any other position, vacuum is not applied to outside/recirculation door vacuum motor and outside air is allowed to enter vehicle.