When Jeffrey Shasteen walked into his Palm Beach Gardens, Fla., home for the last time, he carried with him the smart key for his 2009 Hyundai Genesis.

The 61-year-old had just parked the vehicle — which could be started with the press of a button as long as the key fob was close enough — in a garage on the ground floor of his home. He went to bed the night of Friday, Nov. 7, 2014, not realizing the car wasn’t turned off, according to a lawsuit his children filed in Palm Beach County Court.