I have an 04 Ram 2500 which has the 7 pin style connector for trailers, my question is when I begin pulling an open trailer that has electric brakes do I need anything else for the trailer brakes to work? Do I need a brake controller or is that a built in feature from the factory?

It should have a factory plug underneath the dash for you to plug a controller in. You can pick one up at Advance, Napa, or a million places on line. Yer lookin' at 40 bucks low end. Considerin' the date of your post you hopefullyfigured itout already. But just in case.....