Four Plug Trailer Wiring Diagram

If you’re planning to haul a trailer, it’s essential to have a good understanding of the wiring system. One of the most common types of trailer wiring is the four plug trailer wiring diagram. This system is used for small and medium-sized trailers, and it’s compatible with most vehicles. In this article, we’ll discuss everything you need to know about the four plug trailer wiring diagram.

What is the Four Plug Trailer Wiring Diagram?

The four plug trailer wiring diagram is a system that connects the trailer’s electrical components to the towing vehicle. It consists of four wires that are color-coded for easy identification. The wires are as follows:

Wire Color Function
Brown Tail lights
Yellow Left turn signal
Green Right turn signal
White Ground

The four plug trailer wiring diagram is also known as the basic wiring system as it only provides power to the trailer’s basic lighting functions.

How to Install Four Plug Trailer Wiring Diagram?

Installing a four plug trailer wiring diagram is a simple process that can be done in a few steps. Here are the steps:

Step 1: Gather the Required Tools and Materials

Before starting the installation process, ensure you have the required tools and materials. You’ll need a wire stripper, wire cutter, crimping tool, electrical tape, and the four plug trailer connector.

Step 2: Cut the Wires to Length

The first step in installing the four plug trailer wiring diagram is to cut the wires to the required length. Ensure that the wires are long enough to reach the trailer’s electrical components and the towing vehicle’s connector.

Step 3: Strip the Wire Ends

The next step is to strip the wire ends using a wire stripper. Ensure that you strip enough insulation to expose the conductor.

Step 4: Crimp the Connectors

The next step is to crimp the connectors onto the stripped wire ends. You’ll need a crimping tool to do this. Ensure that the connectors are tight and secure.

Step 5: Connect the Wires to the Trailer and Towing Vehicle

The last step is to connect the wires to the trailer’s electrical components and the towing vehicle’s connector. The brown wire is connected to the tail lights, the yellow wire to the left turn signal, the green wire to the right turn signal, and the white wire to the ground. Ensure that the connections are tight and secure.

FAQs

Q1: What is the difference between a four plug and a seven plug trailer wiring diagram?

A: A four plug trailer wiring diagram only provides power to the trailer’s basic lighting functions, while a seven plug trailer wiring diagram provides power to additional electrical components such as brakes, reverse lights, and the battery.

Q2: Can I use a four plug trailer wiring diagram on a large trailer?

A: No, a four plug trailer wiring diagram is only suitable for small and medium-sized trailers that have basic lighting functions. Large trailers require more power and therefore require a seven plug trailer wiring diagram.

Q3: What should I do if one of the trailer’s lights is not working?

A: If one of the trailer’s lights is not working, check the wiring connections, and ensure that they are tight and secure. Also, check the bulb and replace it if necessary.

Q4: Do I need any special skills to install a four plug trailer wiring diagram?

A: No, installing a four plug trailer wiring diagram is a simple process that can be done by anyone with basic wiring skills. However, if you’re not confident, it’s advisable to seek the help of a professional.

Q5: Can I tow a trailer without a wiring system?

A: No, it’s illegal to tow a trailer without a wiring system. The trailer’s lights are essential for signaling the towing vehicle’s movements and ensuring that other road users can see the trailer.

Conclusion

A four plug trailer wiring diagram is an essential wiring system that connects the trailer’s basic lighting functions to the towing vehicle. It’s easy to install and suitable for small and medium-sized trailers. Ensure that you follow the correct installation procedure and check the wiring connections before hitting the road.