Positioning motor for recirculated air operation 8Z1819453B

Air flow flap control motor V71 is located under the passenger compartment behind the air blower - more on the right side sitting on the seat. It regulates the fresh air supply by opening or closing the flap under the cabin filter.

The most common problem of the V71 error is a defective potentiometer, which serves as a sensor for the position of the drive rod - based on the signal from this potentiometer, the air conditioner analyzes the current angle of rotation of the output shaft on which the rod is mounted and, depending on the required angle, rotates the motor to one side or the other. The moving part of the potentiometer, through metal contacts, slides on conductive paths that are coated with graphite (one slides on the inner ring, the other on the outer ring). Often, the repair involves simply cleaning the potentiometer of graphite filings and re-lubricating the sliding areas (however, this usually only helps in the short term and eventually the motor has to be replaced).

Another common reason for a stuttering or knocking motor is chipped teeth on the yellow sprocket.