Ok where to start. Lol

Basically there is a motor in the heater box that controls where the air blows.(ie. Head, head/feet, feet, feet/defrost, and defrost) and theres a turn **** selector switch which leads multiple wires to a connector. This connector in turn connects to the two wire connector from the mode selector. I am looking for how this all works. Is there a pcb that determined your selection via turn **** and sends a certain current to motor? If so what would the currents be?
Or does it just send a positive pulse each time you turn clockwise and a negative pulse each time you turn counter clockwise?
Im assuming it uses a reverse polarity relay setup of some sort?
Any insight to this would be awesome. Sorry for my poor explanation as it is hard to explain something you dont quite understand lol.