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Audi E-Tron Brake Booster Corrosion Issue

NHTSA campaign 21V707000 · Reported Sep 13, 2021 · Volkswagen Group of America, Inc.

high How serious is it? About this label

Losing ABS, stability control, and brake assist can increase the effort and distance it takes to stop the vehicle, which raises the risk of a crash. The notice does not tell owners to stop driving.

Key facts

NHTSA campaign number	21V707000
Reported to NHTSA	Sep 13, 2021
Manufacturer	Volkswagen Group of America, Inc.
Part affected	Service Brakes, Hydraulic
Vehicles covered	1 model/year combination, model years 2021
Do-not-drive advisory	No
Park-outside advisory	No
Repair	Free at any franchised dealer

What's wrong, in plain English

Certain 2021 Audi E-Tron Quattro and E-Tron Sportback Quattro vehicles may develop corrosion inside the brake booster. Over time, this corrosion can cause several systems to stop working, including the Anti-Lock Brake System (ABS), Electronic Stability Control (ESC), the speedometer display, and brake assist. This means multiple safety systems tied to braking could be affected at the same time in these vehicles.

What you should do

1. Check your VIN at nhtsa.gov/recalls to confirm your vehicle is affected.
2. Contact your dealer or Audi customer service at 1-800-253-2834 to schedule the repair.
3. The brake booster replacement is done free of charge.

Where do I find my VIN, and what do I tell the dealer?

Your VIN is the 17-character code on the lower left of the windshield, on your registration and usually on your insurance card. Enter it at nhtsa.gov/recalls to see whether this recall is still open on your car. When you call the dealer, say you have an open safety recall and give them NHTSA campaign number 21V707000. More in how recalls work.

Affected vehicles (1)

2021 Audi E-TRON

Who to contact

Audi — official Audi recall lookup

Customer service: 1-800-253-2834

Any franchised dealer for the brand can do the repair. Phone numbers are taken from manufacturer sites and recent NHTSA notices; if one has changed, the number in your own recall letter is the one to use.

The bigger picture

Audi Brake Recalls Cover Pedal Detachment and Reduced Braking · all 8 Audi recalls in this area

Other Audi E-TRON recalls

Dec 19, 2025Audi rearview camera may fail to show imagemedium
Aug 19, 2024Audi E-Tron Brake Pedal May Detachcritical
Dec 20, 2023Audi E-Tron High-Voltage Battery May Overheatcritical
Dec 13, 2023Audi portable charging cables can overheat and cause firecritical
Oct 26, 2022Audi Rearview Camera Display May Stop Workingmedium
Oct 5, 2022Audi backup camera screen may go blank in reversemedium

All 11 E-TRON recalls

Official notice

Component: SERVICE BRAKES, HYDRAULIC
Summary: Volkswagen Group of America, Inc. (Audi) is recalling certain 2021 Audi E-Tron Quattro and E-Tron Sportback Quattro vehicles. Corrosion in the brake booster may cause the Anti-Lock Brake System (ABS), Electronic Stability Control (ESC), speedometer display, and brake assist to stop functioning.
Safety risk: A loss of braking assist, ABS, and ESC will increase the effort and distance required to stop, increasing the risk of a crash.
Remedy: Dealers will replace the brake booster, free of charge. Owner notification letters were mailed September 30, 2021. Owners may contact Audi customer service at 1-800-253-2834. Audi's number for this recall is 47R7.

Verify your specific vehicle by VIN at nhtsa.gov. Recall repairs are free of charge by law.