Help! The flat four and seven round electrical plug-ins on my 2002 Supercrew are not working right. On both the left turn signal, headlight, and brake light dont work. The right turn, head, and brake lights do work on both. First thought was a loose wire, but why would it not be working on both plug-ins?

Also, does anyone know which color wire does what?

 

This might be some help; http://www.etrailer.com/faq/wiring.asp

Here's another one; http://www.accessconnect.com/trailer_wiring_diagram.htm

They have some of the same stuff.

Hope this helps.

 

Check your fuses...the running lights, left turn, right turn, trailer power, electric brakes all have their own fuses in the truck.

 

I work for a trailer company...here ya go..

4 pin flat....white----ground
brown---running lights
green---right turn/right brake
yellow--left turn/brake

7 pin round RV

starting in the 11:00 position looking at the truck connection

11:00 Running lights--brown
1:00 trailer Positive--red
3:00 right turn/brakes--green
5:00 trailer brakes--blue
7:00 negative/ground--black
9:00 left turn/brakes--yellow
center post reverse lights--orange/white

These are trailer color wires, not truck colors.

I hope this helps......