What Would Cause Sparks When Trailer Safety Chains are Connected

Question:

I have an old brake controller 2002 and a two year old Forest River 17 foot trailer. I use a 7 pin connector. I just recently installed a weight distribution system not sure if that played a role. I recently connected the trailer and when I did I got sparks from where the chains connected to the hitch. Odd. That seems to have fried the brake controller. I checked all the fuses and they are all still good, so I think the controller has failed. I plan to get a new progressive controller from you and a Hopkins HM40920 just because thats all broken up on my truck. However, I still dont know what would have cause the sparks. Everything was wet because it was raining cats and dogs. Any thoughts?

asked by: Matt S

Expert Reply:

You have a short on the trailer wiring most likely between the 12 volt accessory circuit, the frame of the trailer, and the brake output circuit of the brake controller. You'll need to go over the wiring of the trailer looking for any obvious signs of a short and fix as needed.

expert reply by: Jameson C