my audi aircon has never worked, but the heaters not much good either.
One of the air flaps packed up, so couldnt get cool air in the car. Theres 5 of these motor/flaps, one is impossible to get at. It wasnt that one though, so the glove box came out, and i took the motor off, and took it apart. You have to hold a plastic clip open with one hand, open the next clip with the other hand, while holding it and opening the next clip with another hand.
the gear was stuck but freed easily. The motor worked, the pot resistance was good, it was put back together and didnt work again
i stripped it right down,sprayed all the plastic gear with silicon oil and reassembled it. The gear was sticking in one place, and i couldnt see why I triple checked everything, sprayed it some more and put it back together and back in the car and reset the values and tested it with the software.
Its still making some clicking noises, but the car is a lot cooler,and hopefully wont go wrong again, fingers crossed. If it does i shall disconnect it and keep the flap open