Air Distribution Control
WARNING: This page is about a different car, the 2006 Land Rover Range Rover Sport. However, it is still accessible from the selected car via links, so may be relevant.
When the A/C is in the automatic mode, the ATC module automatically controls air distribution according to a comfort strategy. Automatic control is overridden when one of the manual modes is selected. Air distribution remains manually controlled until the automatic mode is selected again. The distribution doors are operated by two stepper motors, which are controlled by the ATC module using LIN bus messages.