Fresh/Recirculated Air Door
WARNING: This page is about a different car, the 2002 Mercury Villager. However, it is still accessible from the selected car via links, so may be relevant.
Actuator is located behind right side of instrument panel, on plenum. Actuator uses output signal from Electronic Automatic Temperature Control (EATC) module to position fresh/recirculated air door. An internal potentiometer in actuator sends variable voltage back to EATC module to indicate door position.