This happened to me recently and my or may not be your problem but worthwhile.
The top part of the middle spring in one of the GI sockets near the flippers broke off (just a few winds of the middle spring) and was a perfect wedge between the middle and the socket to cause a short. Without actually looking INSIDE the socket from above, I NEVER would have found this.
Did you notice if any GI bulbs were out or flickering when you operated the flippers? If so, check that socket. Other than that, check each socket one by one, particularly by the flippers that are subjected to the most vibration.
Mequon, WI
