Temperature Blend Door Actuators
WARNING: This page is about a different car, the 2005 Lincoln Navigator and 2005 Ford Expedition. However, it is still accessible from the selected car via links, so may be relevant.
The dual-zone EATC system utilizes two temperature blend door actuators to control two separate temperature blend doors that independently vary the LH and RH side temperature settings, as desired. The temperature blend door actuators:
- are located on the plenum chamber.
- move the temperature blend doors on command from the dual-zone EATC module.
- contain a reversible electric motor and a potentiometer. The potentiometer wiper is connected to the actuator output shaft and moves with the output shaft to indicate the position of the temperature blend door.
- receive a reference voltage to one end of the potentiometer. The voltage available at the wiper indicates the position of the potentiometer. The expressed value of the actuator wiper voltage is sent to the dual-zone EATC module and is matched with an expected wiper voltage value.
The dual-zone EATC module then drives the actuator motor in whichever direction is necessary to make the actuator wiper voltage match the expected dual-zone EATC module wiper voltage value.