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Trailer Wiring Information
Trailer Wiring Information

Trailer Wiring Installation Tips

By law, trailer lighting must be connected into the tow vehicle's wiring system to provide trailer running lights, turn signals and brake lights. This is accomplished by tapping into the tow vehicle's electrical harness to transfer power to the trailer wiring system. Connectors are used between the two to allow disengagement when not towing.

Trailer Connectors

Various styles of connectors are available with four to seven pins to allow 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.

The male end is mounted on the vehicle side and the female on the trailer side.

4 Way Trailer Connectors

Flat, molded connectors are available allowing the basic hookup of the three lighting functions and ground. Round 1-1/4" knock-out style can be permanently mounted directly onto all Hidden Hitch products or onto a separate plug mounting bracket. This provides a clean installation and avoids the potential problems associated with leaving a plug dangling from the rear of the towing vehicle.

6 Way Trailer Connectors

Round 1-1/4" diameter metal connectors are available that allow 1 or 2 additional functions such as back up lights and electric brakes. These can be mounted on all Hidden Hitch products.

6 Way Trailer Connector

7 Way Trailer Connectors

Additional pins for auxiliary power, trailer battery charging etc. are available using larger 2" diameter, round connectors. Typically these are needed for larger trailers and can be mounted directly in the bracket mounted on every Class III and IV Hidden Hitch.

7 Way Trailer Connector
trailer wiring diagram
Welcome to Michigan Truck Spring & TruckSpring.com

Since 1926, Michigan Truck Spring has been installing and using the same high quality truck parts that you'll find on our website. In fact, we install everything we sell, and have been selling online as TruckSpring.com since 2001.

Whether you're looking to overhaul your truck suspension, or make a minor repair, our mission is simple - to make sure you have the quality parts you need, and to become your trusted source for truck parts.

Located in the heart of the Midwest, Michigan Truck Spring employees are trained technicians in truck parts and repair. We're here to help, whether it's selecting the right product for your vehicle, an installation question, or a maintenance question, we'll help you through your project. We work hard to make sure you get the right parts for the job. You won't find a company more passionate about truck parts than Michigan Truck Spring.