For the life of me I cannot find the thread that implies that the OEM wiring harness does more than just provide wiring for either a 4 pin or 7 pin trailer attachment. The thread said something like the factory wiring activates the extra radiator fan and changes the transmission's shift points to enhance towing. Sounded kinda fishy to me, but maybe I'm wrong. I was waiting for the 4-pin harness that's currently backordered from Hidden Hitch but if it's true that the OEM harness does more than just provide lighting for the trailer, I'll pony up the extra dough and order it from College Hiils Honda or H and A. Please, someone that actually knows, help me figure this out.