Troubleshooting New Trailer Wiring that Shorts Out Running Light Circuit Fuse

Question:

I have an issue with my wifes horse trailer. I ran all new wires, new lights, and all worked great. Parked the trailer, she hooks up today because shes taking a horse to the vet. Not tail lights, we have brake and turn signals. I found out that she had plugged in the 7 way upside down. I removed it, replaced the fuse, plugged it in, keeps blowing the tail light fuse. Help!!

asked by: Robert H

Expert Reply:

It would be almost impossible to install a 7-way connector upside down as there is a notch on the top of the connector that would prevent it from fitting if installed in a different orientation. I attached a picture that points out where that is. This is also true on the more common 6-way connectors that are found on horse trailers.

So you either have a short on the running light circuit of your trailer or you are overdrawing the circuit. Since you installed new lights I would be inclinded to believe that the problem is a short in the wiring and you would want to trace the circuit back from the connector to the new wiring and lights looking for any exposed wire touching metal and fix as needed.

expert reply by: Jameson C