7 Pin Round Trailer Plug Wiring Diagram

7 Pin Round Trailer Plug Wiring Diagram

When it comes to towing a trailer, one of the most important components is the trailer plug. A 7 pin round trailer plug is one of the most common types of trailer plugs used in Australia. It is important to have a proper understanding of how to wire a 7 pin round trailer plug to ensure that the lights, brakes and other features of the trailer are working properly. In this article, we will discuss the wiring diagram for a 7 pin round trailer plug.

What is a 7 Pin Round Trailer Plug?

A 7 pin round trailer plug is a type of trailer plug that has seven pins or prongs, which are used to connect the electrical circuit of the trailer to the tow vehicle. The pins are designated for different functions, such as tail lights, brake lights, turn signals, and so on.

Each pin is connected to a wire that runs from the trailer to the tow vehicle. The wiring of a 7 pin round trailer plug is standardized, so that it can be used with any type of trailer and tow vehicle that has a compatible plug.

The Wiring Diagram for a 7 Pin Round Trailer Plug

The wiring diagram for a 7 pin round trailer plug is as follows:

Pin Function Wire Color
1 Ground White
2 Tail Lights Brown
3 Left Turn/Brakes Yellow
4 Right Turn/Brakes Green
5 Electric Brakes Blue
6 Auxiliary/Back-up Black
7 12V Power Red

Pin 1: Ground

The first pin of a 7 pin round trailer plug is the ground pin. This is connected to the trailer’s frame and is used to complete the electrical circuit of the trailer.

The wire color for this pin is white. It is important to ensure that the ground wire is securely connected to the trailer frame to prevent any electrical issues.

Pin 2: Tail Lights

The second pin of a 7 pin round trailer plug is used for the tail lights of the trailer. These are the lights that are turned on when the towing vehicle’s headlights are turned on.

The wire color for this pin is brown. It is important to ensure that the tail light wire is connected to the correct circuit of the trailer’s lighting system.

Pin 3: Left Turn/Brakes

The third pin of a 7 pin round trailer plug is used for the left turn signal and the brake lights of the trailer. This pin is also used for the brake controller on the towing vehicle.

The wire color for this pin is yellow. It is important to ensure that the left turn/brake wire is connected to the correct circuit of the trailer’s lighting system.

Pin 4: Right Turn/Brakes

The fourth pin of a 7 pin round trailer plug is used for the right turn signal and the brake lights of the trailer. This pin is also used for the brake controller on the towing vehicle.

The wire color for this pin is green. It is important to ensure that the right turn/brake wire is connected to the correct circuit of the trailer’s lighting system.

Pin 5: Electric Brakes

The fifth pin of a 7 pin round trailer plug is used for the electric brakes of the trailer. This pin is connected to the trailer’s electric brake system, which is controlled by the brake controller on the towing vehicle.

The wire color for this pin is blue. It is important to ensure that the electric brake wire is connected to the correct circuit of the trailer’s brake system.

Pin 6: Auxiliary/Back-up

The sixth pin of a 7 pin round trailer plug is used for the auxiliary or back-up lights of the trailer.

The wire color for this pin is black. It is important to ensure that the auxiliary or back-up wire is connected to the correct circuit of the trailer’s lighting system.

Pin 7: 12V Power

The seventh pin of a 7 pin round trailer plug is used for the 12V power supply of the trailer. This pin is connected to the trailer’s battery, which provides power to the trailer’s electrical system.

The wire color for this pin is red. It is important to ensure that the 12V power wire is connected to the correct circuit of the trailer’s electrical system.

FAQ

What size wire should be used for a 7 pin round trailer plug?

The size of the wire that should be used for a 7 pin round trailer plug depends on the current rating of the circuits that it is connected to. Generally, a 14-gauge wire is suitable for most circuits, but a heavier gauge wire may be required for circuits that draw more current, such as the electric brakes.

Can a 7 pin round trailer plug be used with a 5 pin flat connector?

No, a 7 pin round trailer plug cannot be used with a 5 pin flat connector. The wiring of these connectors is different, and they are not compatible with each other.

What is the difference between a 7 pin round trailer plug and a 7 pin flat trailer plug?

The main difference between a 7 pin round trailer plug and a 7 pin flat trailer plug is the shape of the connector. The wiring of these connectors is the same, but the shape of the connector is different. A 7 pin round trailer plug is more common in Australia, while a 7 pin flat trailer plug is more common in North America.

Can a 7 pin round trailer plug be wired incorrectly?

Yes, a 7 pin round trailer plug can be wired incorrectly. It is important to ensure that the wiring of the plug is done correctly to prevent any electrical issues or safety hazards when towing a trailer.

What tools are needed to wire a 7 pin round trailer plug?

The tools that are needed to wire a 7 pin round trailer plug include a wire stripper, crimping tool, electrical tape, and a volt meter.

Overall, wiring a 7 pin round trailer plug is a relatively simple process as long as you have a proper understanding of the wiring diagram and the tools that are needed. By following the steps outlined in this article, you can ensure that your trailer is properly wired and is safe to tow.