Towing Issues: wiring issues, high beams, trailer brakes

Question
Hi, I have a wiring issue that I hope you can help with.  The problem revolves around losing all trailer lights (markers and brakes) when either using high beams or putting vehicle in reverse.  I had this problem in the past, so I recently completely rewired my trailer.  No luck fixing these particular problems.  These problems only seem to arise when hooked to my truck, as when it is attached to a different tow vehicle this does not occur. A note that might help, this evening I noticed that as I turned my high beams on my brake controller light went red for a split second and then went out.  When I turn the high beams off or switch out of reverse all things seem to operate correctly.  I believe that the problem originates in the truck itself, but I have no idea where to start looking.  It is a 1996 Dodge 2wd 3/4 ton if that helps.  Thanks for any advice you may be able to offer.  Tim

Answer
while I am no expert on trailer towing issues, it sounds as if the power wire for the trailer brakes is shorting out to some light circuits...

I would suggest that you take it to an Automotive Electrical shop and see if they can find the problem.
Other issue I would look at is to take the plug assembly apart on the truck and look for loose wires or rubbed though wires right at the back of the plug... Beyond that  I am at a loss..