The contact owns a 1997 Jeep Grand Cherokee. The contact stated that while driving at an undisclosed speed, the vehicle inadvertently lost motive power, prompting her to attempt to stop the vehicle. After which, with the brake pedal depressed all the way to the floorboard, the vehicle failed to stop, only coming to a complete stop after going off the road into a drainage ditch and rolling over on its roof. The air bags did not deploy. No warning lights were illuminated. The vehicle was towed from the scene but not taken to the dealer or an independent mechanic. The vehicle was not repaired. A police report was not filed. No injuries were reported. The manufacturer was notified of the failure and referred the contact to the NHTSA Hotline for assistance. The failure mileage was 250,000.