F 350 4WD Super Duty V10-6.8L VIN Z CNG (2003)
Air Door Actuator / Motor: Description and Operation
Electronic Automatic Temperature Control (EATC)
Temperature Blend Door Actuator
The temperature blend door actuator:
^
is located on the top of the plenum chamber behind the glove compartment.
^
moves the temperature blend door on command from the EATC module.
^
contains a reversible motor and 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.
^
applies a 5 volt signal to the ends of the potentiometer. The expressed value of the actuator wiper voltage is sent to the EATC module and is
matched with an expected wiper voltage value. The EATC module then drives the actuator motor in whichever direction is necessary to make the
actuator wiper voltage agree with the expected EATC module wiper voltage value.
Vacuum Control Motors
The two vacuum control motors:
^
are actuated by the ATC solenoid and manifold based on inputs from the EATC module.
^
position the plenum doors to direct system airflow to the vehicles interior as determined by the EATC module settings.
