I installed some LED back-up lights on my trailer about 3 yrs ago. Just pig tailed off the stock backup lights on the trailer. After about 6 months I started having a problem where about half the time when backing the trailer into the lake my fuse would blow for the trailer back up lamps. I was unable to isolate the cause so I just started unplugging my trailer wire harness when I had backed to the waters edge. Well now my fuse is blowing when I go to back into the garage. No water involved. I am showing continuity between ground and the back up lead on the trailer harness. I first disconnected all backup lamps and still show continuity. Trying to isolate I cut the lead to the starboard side backup light with no change.. Then the backup solenoid lead to the trailer, no change. Last, I cut the lead to the Port side backup lights and continuity was finally broken . Before I start back wiring this together, does any body have a suggestion how to solve my dilemma other than run a new+ lead from the harness to the back port side of the trailer?