2021 Audi A7 E Owner Complaints

At approximately 43,044 miles, my 2021 Audi A7 55 TFSI e quattro (PHEV) was diagnosed with a failed N632 coolant changeover valve — a component of the PHEV thermal management heating circuit. The vehicle has a complete, documented service history with no maintenance gaps. The N632 is an electronically controlled valve that routes coolant between the combustion and hybrid/electric circuits and is essential for cabin heating in EV mode, battery pre-conditioning, and engine warm-up. Failure of this valve can result in loss of cabin heat, coolant leaks into the engine bay, and potential cascade of electrical faults if coolant migrates into the wiring harness. The repair estimate is $1,700. The factory warranty, Audi Care plan, and third-party extended service contract (United Car Care Protection Plus) have all denied coverage. This failure on a low-mileage PHEV with full service history suggests a premature component defect in Audi's PHEV thermal management system. I am requesting NHTSA investigate whether this constitutes a pattern of failure across 2021 Audi PHEV vehicles.

NHTSA ID

11734901

Incident

Apr 15, 2026

The warning ‘drive system failure’ appears while driving and tells you to stop the car immediately. This happens randomly while driving on a highway. The engine now makes a higher pitched noise and then the transmission will no go into drive it immediately goes into neutral, the car slows down and you must pull over as you have no control over the car. The gas doesn’t work. There are so many alerts that pop up with a malfunction- parking brake, transmission, distance warning, audi presense warning, tire pressure malfunction, transmission malfunction. BEFORE this- There was an issue found when a check engine light appeared after the car failed emmissions testing. Control Pilot Circuit High and AC refrigerant pressor sensor B circuit failures listed. The car went to Audi and they said it was an air conditioning issue and other faults. The cleared the faults and signed off on the emmissions paperwork. I told Audi of the issue when getting it serviced- they could not replicate the random drive system failure alert. Again the same issue- bring it to audi- they had it for a week or so- still cannot replicate the issue. A few weeks later while driving on I91, the driver system alert comes on and there was a high pitched sound car goes into neutral- I have no control over the vehicle and coast down 2 roads and into a driveway of a volkswagen dealership in an unsafe area of Hartford. I then started the care up and took it to Audi of East Hartford. The replicated the issue they said and replaced the entire EOC unit for almost $7000. They had the car for a month. Then after having it back a couple of weeks it randomly does it again and restarting the car would reseg it only once and then another alert and the car dies on the highway and I again lose control and pull over to the shoulder. VERY VERY unsafe. The car just dies randomly on a highway. It happened in May of 2025, June and July. July 15 was the most recent immediately after being ‘repaired’.

NHTSA ID

11673863

Incident

Jul 15, 2025