Air Door: Description and Operation

The heater control panel receives battery voltage at all times through fuse 47. With the ignition switch in ON (II), voltage is supplied to the heater control panel through fuse 17. The control panel is grounded at G401.

The heater control panel controls the air delivery motors, and supplies a 5 VDC reference voltage to the air mixture control motor.

The air mixture and mode control motors each receive inputs from the heater control panel. The air mix motor regulates the mixture of cold and hot air by varying the position of the heater-evaporator door.

The mode control motor controls the direction and volume of cutlet air. The air flow can be directed to the dashboard vents or the corner vents.
Both the air mixture control motor and mode control motor are grounded by the heater control panel.

The recirculation control motor receives battery voltage through fuse 17 when the ignition switch is in ON (II). It regulates the position of the fresh/recirc door, and is controlled by two position inputs from the heater control panel ("Recirc" and "Fresh").