Airflow Mode Door Actuator

The airflow mode door actuator uses a cam and lever assembly to position the airflow mode doors on command from the dual-zone EATC module. The mode door actuator contains a reversible electric motor and potentiometer. The potentiometer allows the dual-zone EATC module to monitor the position of the airflow mode doors. The potentiometer circuit consists of a 5-volt reference signal connected to one end of a variable resistor, and a signal ground connected to the other. A signal return circuit is connected to a contact wiper, which is driven along the variable resistor by the actuator shaft. The signal returned to the dual-zone EATC module from the contact wiper indicates the position of the airflow mode doors.