NHTSA Complaint #11699448 — 2017 VOLVO XC90

On November 5, 2025, while driving my 2017 Volvo XC90, I experienced a sudden and dangerous loss of braking assist. When I pressed the brake pedal, I heard a loud hissing noise coming from under the dashboard, and the car would not stop. The brake would not work and the vehicle would not slow or stop unless I stood up and used my full body weight to press it. A licensed mechanic inspected the vehicle and confirmed this is consistent with loss of vacuum pressure from the brake booster/failure of the vacuum brake booster, the component that provides power assist to the braking system. The booster, brake pump, hose from booster to pump and brake pedal clip were replaced, with an estimated cost of $2,858. The mechanic also advised that this failure is not uncommon in Volvo XC90 models. After the incident, I researched similar complaints and found numerous reports on NHTSA and [XXX] describing **identical symptoms—hard brake pedal and hissing sound due to vacuum booster failure—**in the 2016–2019 XC90. For example, one owner reported “hard pedal, no assist, hissing sound behind dash” [XXX] , Volvo XC90 2017 Brakes section, accessed Nov 2025). No warning lights or error messages appeared before or during the event. The problem occurred suddenly and without prior symptoms. This defect posed a serious safety risk to me, my passengers, and other drivers, as it severely reduced braking ability and required excessive force to stop the vehicle. Under other conditions, this issue could easily have resulted in a crash. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)