I have a 2007 Dodge Nitro, 4.0 with a factory trailer hitch and harness. I have a trailer brake controller that I installed when I bought the vehicle. Everything worked fine for years. I noticed the femalel connector on trailer had broke but was still working. I had to jiggle the plug and everything worked. I changed installed a new plug and tested my lights and everything worked. I pulled the vehicle forward to test the trailer brakes and they worked once. I noticed there was no reading on the brake controller that lets you know how much brake i'm applying to trailer. I check the fuses for the circuit and they are all good

I called the dealer to find out if there is a module in the circuit and he said no. Everything worked fine until I changed the plug.

 

possibly might not have a good ground