See Tesla Model S driver claims his car crashed into a trailer on its own, Tesla says ‘Summon’ was activated Tesla says driver activated Summon on his parked car causing it to hit parked trailer in front of it. Driver says he didn't activate Summon and the car moved on its own while he was away from the car in a store. It appears the S sensors could not detect the parked trailer bed because it was too high off the ground. Hard to be sure where the blame lies here. I think possibly on both parties, but driver denies that he ever saw the car move after he parked it. Though clearly the car did move.