I like to use my car as a phone charger but I don't always have time to sit in my car with the engine running to charge it. For Ford and any other consumer electronics producer, leave the 5v on! Or at least give us a setting to do that. Unless there is a setting, I'm going to have to hack something. The accessory 12v does seem to stay on but I'm going to have to check that with the key away from the car.