Odd situation. Earlier in the week I installed power to a dock to operate 2 jet ski lifts. I completed the install and test operated both units(up and down full lift distance). I get a call this morning from the owner who tells me one lift is tripping the GFCI breaker as soon as the key switch is activated. If he removes the controller and motor and plugs it into a non protected outlet in the garage it works fine. Any clue as to what could happen between Wed. and now with no one doing anything with the lift in the interim???? Thanks.