Theory Of Operation

WARNING: This page is about a different car, the 2012 RAM Pickup. However, it is still accessible from the selected car via links, so may be relevant.

After the initial installation of the A/C Heater Control, the controller is calibrated to each individual blend/mode door actuator. These calibrations are stored as in the number of pulses it takes to move the door from one stop to another. The A/C Heater Control drives the Door Actuators by the use of Door Driver circuit and a Common Door Driver circuit and monitors all door actuator pulses to detect door movement in both directions. Most of the door actuators share a common door driver circuit but each door actuator has its own unique driver circuit. The Defrost Door Actuator does not share a common door driver circuit because defrost mode is used as a system default mode if there is a system malfunction. Due to shared circuitry, similar DTC's can set at the same time for multiple actuators depending upon the type of circuit malfunction, its location, and the direction the actuator is moving when the malfunction is present.