scooter. Mackie , I think, has described "current" which moves (voltage does not). So the drain check above will report on problems along the path. Perhaps careful removal of the switch and "beeb" checks or resistance checks while wiggling the key on the positions. Switches have contacts which wear down and can get sloppy. Corrosion can produce conductor paths where you do not want them...top of battery or bracket. Hour meter stuck on etc.