My wife was driving in the centre lane of a motorway when the parking brake came on as she was travelling at70mph.,immediatly stopping the car. Fortunately following traffic avoided and she was able to restart the stalled car and get onto hard shoulder. The button is inactive and possibly broken(it was fine on starting out), having occurred since or during the incident. She is adamant that she had not touched the button, which I believe. This is very worrying, car is just over 3yrs old, fully serviced by Hyundai. Is booked in at dealership next week. Has anyone had a similar problem in what could have been a fatal incident.