I was driving down a slight hill in 1/2 inch of snow at 5MPH and when I tired to gently brake as I descended the hill, the brake pedal had no resistance and went flat to the floor. I had no brakes. I then tried to steer towards the side of the road and the steering wheel completely locked up and I was not able to steer. I slid 150 feet down the hill and into a ditch. No brakes and no steering. There must have been a failure of some kind. Terrifying.