The contact owns a 2021 GMC Acadia. The contact stated that while driving at 30 MPH, traffic stopped abruptly, and the brake pedal was depressed to the floorboard; however, the vehicle continued to accelerate while the Forward Collision Avoidance warning feature activated with a red warning light on the instrument panel. The contact attempted to steer off the road to avoid a collision; however, the vehicle crashed into the vehicle ahead, resulting in a three-vehicle collision. The air bags did not deploy upon impact. Another driver involved claimed unknown injuries, and the contact sustained whiplash but did not seek medical attention. Police were called, but a police report was not filed at the scene. The vehicle was towed to an independent tow yard. The manufacturer was notified of the failure and stated that the VIN was not included in a recall. The failure mileage was approximately 64,000.