It should work fine if you understand automotive wiring. Your 4 wires are for
1] & 2] left/right turn signal lights, and when both left and right are hot at the same time, that's your stop lights.
3] tail/running lights, and
The three wires you will add are for
5] trailer brake control,
6] hot 12-volt wire to charge the RV battery, and
7] backup lights on the trailer. Some folks use that backup light wire for something else, and most folks don't even connect it to anything (very few trailers have backup lights.)
The trailer brake wire is somewhat complicated to hook up. Do a search on etrailer.com and maybe you can find instructions. The simplest way is to tap into a brake light. If the brake light is on, then the driver wants the trailer brakes to work too. And you must use diodes and resisters and a fuse and all that electronic stuff I know nothing about. So do more research. But knowing what the 7 wires are for should get you started.
Last edited by smokeywren; 06-30-2014 at 08:52 PM.