The contact owns a 2015 Kia Optima. The contact stated their daughter was driving at 55 mph, the vehicle in front of the driver slammed on their brakes for a complete stop which caused the contact to depressed on the brake pedal however the vehicle did not stop or slow down causing the driver to crash into the rear of the vehicle in front. The driver-side air bag did deploy. The front end and hood were bent. No one was injured. There was no medical treatment at the scene. A police report was filed. The vehicle was towed to a collision center. The vehicle was not diagnosed or repaired. The manufacturer was not made aware of the failure. The failure mileage was approximate 180,000.