I have a 06 2500 4x4 and im having trouble hooking up a 7 flat for my gooseneck trailer. As of right now there is a 4 flat and a small plug with two wires connected to it. Ive done a little research and found out that there should be a LARGE plug that runs with the 4 flat to the rear, ive looked and MIA. All i have is a ton of wires, 4 flat, and small plug at rear of truck. From the diagrams ive seen the small plug as nothing to do with 7 flat, what's it's purpose ? Im trying to stay away from any splicing any wires and use the plug that SHOULD be there. Any help or suggestions ?

 

Well first your new 7 plug should have a diagram showing what each pin should be, an "industry standard", now find and identify each wire from your mess of wires, left, right, tail, ground, lights, brake and a hot 12Volt (battery power).

Hook up each one to the proper pin as indicated with your instructions, if you don't have the instructions any trailer supply can help or maybe the internet.

 

J,

Sounds like your truck did not have the tow harness, dodge does a kit for this it is being discussed on another thread my post starts at 25 ..go there it will save me some retyping..

https://www.dieseltruckresource.com/...=234309&page=2

 

Here is another wiring link. I'm guessing that you are talking about 7 flat pins, not a flat connector. There are also a lot of adapters out there to convert from 7 to 6, etc.

http://www.etrailer.com/faq_wiring.aspx