F 150 2WD Pickup V8-5.4L SOHC VIN 5 (2004)
Air Door Actuator / Motor: Description and Operation
Electronic Manual Temperature Control
TEMPERATURE BLEND DOOR ACTUATOR
The temperature blend door actuator:
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is located on the heater core and evaporator core housing.
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moves the temperature blend door on command from the EMTC module.
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contains 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.
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applies a 5 volt signal to one end of the potentiometer and ground to the other. The voltage available at the wiper indicates the position of the
potentiometer. The expressed value of the actuator wiper voltage is sent to the EMTC module and is matched with an expected wiper voltage
value. The EMTC module then drives the actuator motor in whichever direction is necessary to make the actuator wiper voltage agree with the
expected EMTC module wiper voltage value.
MODE DOOR ACTUATORS
The three mode door actuators:
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include the air inlet door, floor/defrost door and panel door actuators.
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direct system airflow to the vehicle interior as determined by the function selector switch.
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contains 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 mode door.
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applies a 5 volt signal to one end of the potentiometer and ground to the other. The voltage available at the wiper indicates the position of the
potentiometer. The expressed value of the actuator wiper voltage is sent to the EMTC module and is matched with an expected wiper voltage
value. The EMTC module then drives the actuator motor in whichever direction is necessary to make the actuator wiper voltage agree with the
expected EMTC module wiper voltage value.
