Heritage Machine & Welding Bloomington IL

Heritage Machine & Welding

Trailer Wiring
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Trailers are required to have at least running lights, turn signals and brake lights. For complete listing and proper placement go to: http://www.nhtsa.dot.gov/cars/rules/stan dards/conspicuity/Trlrpstr.html

To provide the power and a hook-up for these, the tow vehicle's wires are tapped into. This is accomplished through either a T-One connector (if available for your vehicle) or through hardwiring. The T-One Connector is pre-wired to a 4-pole flat that can adapt to a 6 or 7 way round connector. Hardwiring requires the installer to locate the proper wires in the tow vehicle. To help in this task consult the owner's manual or the chart at the bottom of the page.

Connectors

Various connectors are available from four to seven pins to allow for the transfer of power for the lighting as well as auxiliary functions such as electric trailer brake control, backup lights, etc. Choose a connector that has the required number of pins for the functions required. Also, mount the connector on the vehicle.  Not only will it display a clean look, but a mount is helpful in avoiding the potential problems associated with leaving a connector dangling. 

4-Way Connectors
4-Way connectors are available allowing the basic hookup of the three lighting functions (running, turn, and brake) plus one pin is provided for a ground wire.

4-Way Flat Trailer Connector - *Most Common

4-Way Flat Truck Connector

4-Way Round Trailer Connector

4-Way Round Truck Connector

6-Way Connectors
6-Way connectors are available allowing the basic hookup of the three lighting functions (running, turn, and brake) and besides the ground, two extra pins are available to provide two additional functions.

6-Way Round Trailer End

6-Way Truck End

6-Way Square Trailer & Truck Connectors

The Diagram below shows the proper way to wire the connector to your trailer or vehicle.

Note: The black (12V) and Blue (Electric Brakes) may be reversed to suit trailer. Horse Trailers may use the center pin for 12V hot lead, R.V. trailers use the center pin for electric brakes.

7-Way Connectors
Besides the three main lighting functions, additional pins for auxiliary power, trailer battery charging etc. are available.

Proper way to wire the connector to your trailer or vehicle.

5-Way Connectors
5-Way connectors are available allowing the basic hookup of the three lighting functions (running, turn, and brake) and besides the ground, one pin is available to provide support for another function. Usually the 5-Way Flat is used for trailers with surge brakes. The additional wire is tapped into the backup lights to disengage the trailer's brakes when the vehicle is reversing.

5-Way Flat Trailer End

5-Way Flat Truck End

5-Way Round Trailer End

5-Way Round Truck End

How to Wire 4, 5 or 6 Way Connectors

Wire Color By Manufacturer

Vehicle Manufacturer

Dual Purpose Bulb System

Wire Function

Wire Color

   GMC

Ford

Chrysler

Jeep

Toyota

Honda

Mazda

RIGHT TURN & BRAKE LIGHTS

Green

 Green

Orange W/ Blue Stripe

Brown

Brown

Green W/ Yellow Stripe

Green W/ Yellow Stripe

Green W/ Yellow Stripe

LEFT TURN & BRAKE LIGHTS

Yellow

 Yellow

Lt Green Orange Stripe

Dk Green

Grey W/ Black Stripe

Green W/ Black Stripe

Green W/ Blue Stripe

Black Stripe

TAIL LIGHTS

Brown

 Brown

Brown

Black W/ Yellow Stripe or Black

Blue

Red W/ Green

Red W/ Black Stripe

Green or Black Stripe

GROUND

White

Black

Black or Grey

Black

Black & Black

Black or White

Black

Black

Single Purpose Bulb System

BRAKE LIGHTS

Use Converter

Pink or Lt Blue

Red W/ Green Stripe

White

Blue W/ Black Stripe

Green W/ Red or White Stripe

Green W/ White Stripe

Green or Green W/ Red Stripe

BACKUP LIGHTS

Red

Lt Green

Black W/ Pink

Violet

Brown

-

-

-

ELECTRIC TRAILER BRAKES

Connect To Blue Wire From Brake Controller

Vehicle manufacturers have intermittently changed wiring colors over the years.
It is recommended that a circuit tester be used on the tow vehicles wiring harness to verify that the correct wire has been located for the proper function.