Trailer Wiring

Hello all,

For those of you that need to wire up a trailer or have to occasionally borrow trailers and look at the wiring plugs with disdain (I mean face it they don't make sense, grd is white, +12vdc is black, etc), this is for you.

Plug Types/Application
7 Way - RV Trailers, Horse and Utility Trailers
6 Way - Horse, Stock and Utility
4 Way - Utility Trailers

Columns are: Color, Function, Mark on the plug.

Seven wire Trailer plugs:

Horse, stock or utility trailers:
White = Ground - 1
Blue = Electric Brakes - 2
Brown = Tail and clearance lights - 3
Black = Battery, aux power - 4
Yellow = Left turn/Brake - 5
Green = Right turn Brake - 6
Orange or Purple (not both) = Auxilliary or Reverse - 7

Recreational Vehicle:
White = Ground - 1
Blue = Electric Brakes - 2
Green = Tail and clearance lights - 3
Black = Battery, aux power - 4
Red = Left turn/Brake - 5
Brown = Right turn Brake - 6
Yellow = Auxilliary or Reverse - 7


Six wire trailer plugs:

Horse, stock or utility trailers:
White = Ground - GD
Yellow = Left turn/Brake -LT
Green = Right turn Brake -RT
Brown = Tail and clearance lights - TM
Red or Black (not both) = Battery, aux power - A
Blue = Electric Brakes - S

Recreational Vehicle: (color, use, plug mark)
White = Ground - GD
Brown = Right turn Brake - RT
Green = Tail and clearance lights -TM
Black = Battery, aux power - A
Red = Left turn/Brake - LT
Blue = Electric Brakes - S


Four wire plugs:
White = Ground
Yellow = Left turn/Brake
Green = Right turn Brake
Brown = Tail and clearance lights


Ground should be 10ga.
Others 14 ga

A test light and a 12VDC power source can be handy for trouble shooting.
Best regards
Mike