The contact owns a 2025 GMC Yukon. While the contact's husband was driving at an undisclosed speed, the brake pedal was depressed; however, the vehicle failed to stop as intended. The contact stated that the brake failure warning light was illuminated. The contact’s husband depressed the brake pedal and noticed that the brake pedal was firm and difficult to depress. The contact stated that an error message indicated that the vehicle was decelerating. The contact's husband depressed the brake pedal and the vehicle decelerated to 40 MPH. While the contact’s husband was slowly driving into the driveway at the residence, the brake pedal was depressed; however, the vehicle failed to stop. The contact’s husband immediately shifted the gear shifter into park(P) to stop the vehicle. The contact stated that the failure had occurred while on the way home from a family trip. The vehicle was towed to the dealer and the vehicle was diagnosed with a failed brake master cylinder assembly, a failed brake control module, and a failed brake plunger. The contact was informed that the brake master cylinder assembly, the brake control module, and the brake plunger needed to be replaced. The vehicle was not repaired. The contact was informed that the parts were on back-order. The manufacturer was not made aware of the failure. The failure mileage was approximately 3,150.
NHTSA ODI 11681592