I have a 2014 Ram 2500, when I plug in my 5th wheel the left turn signal and brake light dies not work and blows the fuse. I have had the 5th wheel checked out and it checks out good. I had my truck looked at and was told the truck was good also. What is causing this?

 

Does the fuse blow as soon as the trailer wiring is connected or only once the turn signal is activated / brake pedal is pressed? If only as soon as the bulb request is active, the issue almost has to be with the wiring on the trailer. Do you know someone else with a 5th wheel trailer that you could back up to in order to see if their trailer also causes the fuse to blow? What is the current rating of the fuse that is blowing? Do you have a current meter that you could use to determine the amount of current the trailer is attempting to pull?

-Rod