Tip & How-To about Toyota 4Runner

Trailer Wiring Problems?

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, ground 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

Posted by on

Cars & Trucks Logo

Related Topics:

Related Questions:

1 Answer

Trailer Lights, I have a polarity problem. The LED tail lights on my trailer only work if I reverse the plug-in, any idea on how to fix this polarity problem.


Possibly the person that borrowed your trailer changed some of the wires. Old-type bulbs don't care about polarity, but LEDs do.

Oct 18, 2015 | Cars & Trucks

1 Answer

car to trailer wiring problem


most likely the trailer wires dont match the truck wires. you will need to verify that the truck is wired correctly and then that the trailer is wired to match your truck. problems usually arise after someone has BORROWED a tralier and made the trailer wires match THEIR truck trailer wiring here is standardized but people wire them up any way the can, and it causes problems when that trailer is borrowed or sold.

Oct 03, 2009 | Toyota Land Cruiser Cars & Trucks

Not finding what you are looking for?

2,234 people viewed this tip

Ask a Question

Usually answered in minutes!

Top Toyota Experts

yadayada
yadayada

Level 3 Expert

76848 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

22246 Answers

Jeffrey Turcotte
Jeffrey Turcotte

Level 3 Expert

8582 Answers

Are you a Toyota Expert? Answer questions, earn points and help others

Answer questions

Loading...