Where is the fresh air flap servo motor located in the Audi A6?

[DiEverett]

Audi A6 fresh air flap servo motor is located inside the evaporator assembly with the blower in the front. Common faults and causes of servo motors: Motor powered on, mechanical oscillation: Common causes for such faults include: pulse encoder failure. At this time, check whether the servo system is stable, whether the circuit board maintenance detects stable current, and whether the voltage on the speed detection unit feedback line terminal drops at certain points. If there is a drop, it indicates a faulty pulse encoder, replace the encoder; the pulse encoder universal joint may be damaged, causing the shaft speed to be out of sync with the detected speed, replace the universal joint; the tachogenerator may be faulty. Repair or replace the tachogenerator. In maintenance practice, tachogenerator brush wear and sticking are common. At this time, remove the tachogenerator brush, sand it lightly with steel sandpaper, clean the commutator dirt, and reinstall it properly. Motor powered on, abnormal rapid mechanical movement: When such a servo system fault occurs, while checking the position control unit and speed control unit, also check: whether the pulse encoder wiring is incorrect; whether the pulse encoder universal joint is damaged; check whether the tachogenerator terminals are reversed and whether the excitation signal line is incorrectly connected. Generally, such phenomena should be handled by professional circuit board maintenance technicians, otherwise it may lead to more serious consequences.