NHTSA Complaint #11639800 — 2021 AUDI E-TRON

On five separate occasions across two separate drivers, we have experienced a partial brake failure in this vehicle. We strongly believe this to be a software defect and not a mechanical fault. On the e-Tron, the first portion of the brake pedal swing typically activates the regenerative braking. About mid-way through pressing the pedal, it changes to "real" mechanical brakes. When this brake failure occurs, we get to that midway point and the car lets off the regenerative braking but does NOT apply the mechanical brakes, so the end result is that the more you press the brake pedal, the less it works. Three of these five occasions occurred in one day, so by the time the third time came around, I was really paying attention and I'm very confident this wasn't driver error. In at least one case, the only reason that a crash was avoided is because the automatic braking / forward collision system activated. The vehicle has been inspected by a dealer, who found "No Repairs Recommended". We requested an update to the ABS module software, as this software update is known to resolve multiple other problems with the braking system (see TSBs 2072977, 2061906) but we were denied the update.