When it comes to towing a trailer, it’s important to have the proper wiring to ensure that all the lights and electric brakes are working properly. The 8 way trailer plug is one of the most commonly used connectors for trailers, and understanding its wiring diagram is crucial for safe and efficient towing. In this article, we’ll go over the 8 way trailer plug wiring diagram in detail, including FAQs and tables to make it easy to understand.
What is an 8 Way Trailer Plug?
The 8 way trailer plug is a connector that allows you to attach your trailer’s electrical system to the towing vehicle’s electrical system. It provides power to the trailer’s brake lights, turn signals, tail lights, and sometimes even the electric brakes. The 8 way trailer plug is also known as the Round 8 Trailer Connector and is one of the most versatile and widely used connectors for trailers.
How to Identify an 8 Way Trailer Plug?
The 8 way trailer plug has eight pins arranged in a circular pattern. Each pin has a specific function, allowing for the transfer of power and data between the towing vehicle and trailer. Here’s a breakdown of the pin functions:
| Pin Number | Function |
|---|---|
| 1 | Ground |
| 2 | Electric Brakes |
| 3 | Taillights |
| 4 | Left Turn Signal |
| 5 | Right Turn Signal |
| 6 | Brake Lights |
| 7 | Auxiliary |
| 8 | Backup/Reverse Lights |
Now that you know the pin functions, let’s dive into the wiring diagram.
8 Way Trailer Plug Wiring Diagram
Before we get started with the wiring diagram, it’s important to note that the wiring color codes may vary depending on the manufacturer. Always refer to the manufacturer’s instructions for the correct color codes.
Step 1: Ground Wire Connection (Pin 1)
The ground wire is usually the white wire, and it needs to be connected to the towing vehicle’s chassis or grounded terminal. This will complete the circuit and provide a return path for the electrical current.
Step 2: Electric Brake Wire Connection (Pin 2)
The electric brake wire is usually the blue wire, and it needs to be connected to the electric brake control unit on the towing vehicle. This wire provides power to the trailer’s electric brakes when the brake pedal is pressed.
Step 3: Taillight Wire Connection (Pin 3)
The taillight wire is usually the brown wire, and it needs to be connected to the towing vehicle’s taillight circuit. This wire provides power to the trailer’s taillights, which include the running lights, license plate light, and side marker lights.
Step 4: Left Turn Signal Wire Connection (Pin 4)
The left turn signal wire is usually the yellow wire, and it needs to be connected to the towing vehicle’s left turn signal circuit. This wire provides power to the trailer’s left turn signal light.
Step 5: Right Turn Signal Wire Connection (Pin 5)
The right turn signal wire is usually the green wire, and it needs to be connected to the towing vehicle’s right turn signal circuit. This wire provides power to the trailer’s right turn signal light.
Step 6: Brake Light Wire Connection (Pin 6)
The brake light wire is usually the red wire, and it needs to be connected to the towing vehicle’s brake light circuit. This wire provides power to the trailer’s brake lights.
Step 7: Auxiliary Wire Connection (Pin 7)
The auxiliary wire is usually the black wire, and it can be used for a variety of purposes, such as powering a trailer’s interior lights or charging a trailer’s battery. This wire is optional and may not be present on all trailers.
Step 8: Backup/Reverse Light Wire Connection (Pin 8)
The backup/reverse light wire is usually the purple wire, and it needs to be connected to the towing vehicle’s backup light circuit. This wire provides power to the trailer’s backup lights, which are used when the vehicle is in reverse gear.
FAQs
1. Can I use a 7 way trailer plug instead of an 8 way trailer plug?
Yes, you can use a 7 way trailer plug instead of an 8 way trailer plug. However, you will lose the backup/reverse light function, as well as the auxiliary wire function if present.
2. How do I test my trailer’s wiring?
To test your trailer’s wiring, you will need a multimeter or a trailer tester. Connect the tester to the trailer’s plug and check each pin for the correct voltage and functionality. If any issues are found, refer to the wiring diagram and manufacturer’s instructions for troubleshooting.
3. What do I do if my trailer’s wiring is damaged or needs repair?
If your trailer’s wiring is damaged or needs repair, it’s important to address the issue as soon as possible to ensure safe and efficient towing. You can either repair the wiring yourself using a wiring kit or take it to a professional for repair.
Conclusion
Understanding the 8 way trailer plug wiring diagram is crucial for safe and efficient towing. By following the steps outlined in this article and referring to the manufacturer’s instructions, you can ensure that your trailer’s electrical system is properly wired and functioning correctly. As always, be sure to regularly inspect your trailer’s wiring and connections for any damage or wear and tear.
