Mastering trailer plug wiring is key for the safe and efficient use of your trailer. This guide simplifies the essentials for you.
Understanding Trailer Wiring Colours
In Australia, trailer wiring follows the 12 Pin Flat Plug and Socket standard (AS4177.5-2004). Each wire colour serves a specific function:
- Yellow: Left turn function
- Black: Reverse function
- White: Ground wire
- Green: Right turn function
- Blue: Brake power wire
- Red: Brake lights
- Brown: Rear lamps and marker lights
- Orange: Auxiliary power
- Pink: Additional wires
- Grey: Rear fog lamp
- Violet: Additional functions
Wiring Standards: SAE vs RV
Trailer wiring adheres to different standards:
- SAE Standard: Green for right turn/brake lights, yellow for left turn/brake lights, brown for tail/running lights, white for ground wire, blue for brake controller output, black for battery hot lead, purple for reverse lights.
- RV Standard: Green for tail/running lights, yellow for reverse lights, brown for right turn/brake lights, white for ground wire, blue for brake controller output, black for battery hot lead, red for left turn/brake lights.
Types of Trailer Connectors
- 4-Way Flat Trailer Connector: Basic trailers with running lights, turn signals, and brake lights.
- 5-Way Flat Trailer Connector: Adds reverse function.
- 7-Way Round Trailer Connector: For a range of trailers, adding electric trailer brakes, auxiliary power, and trailer battery charging.
Using Trailer Wiring Harness and Adapters
A Trailer Wiring Harness is essential for connecting electrical components between the tow vehicle and the trailer. Adapters convert different plug types, such as a 7-pin to 4-pin adapter for compatibility between different trailer connections.
Troubleshooting Trailer Wiring
- Core Trailer Wire: Inspect the ground wires, brake power wire, and core trailer harness.
- Common Trailer Wiring Faults: Issues with bad grounds or the tow vehicle’s connectors.
- Circuit Analysis: Use a multimeter to check continuity. Secure connections with electrical tape and ensure no damage to the coating on trailer wires.
Trailer Wiring Diagrams
User friendly trailer wiring diagrams help guide the installation of trailer lights, brake lights, and other electrical components. Understanding wire colours ensures correct connections for safe operation.
Installing Trailer Connectors
- Mounting Brackets: Protect trailer connectors and ensure secure connections to prevent damage and faults with trailer brakes.
- Flat Trailer Plug Wiring: Match wire colours to their functions. Proper installation ensures reliable electrical connection.
Types of Trailers
Different types of trailers include utility trailers, cargo trailers, boat trailers, camper trailers, flatbed trailers, and horse trailers. Each has unique wiring needs, such as hydraulic brakes or additional functions like auxiliary power.
Ensuring Adequate Power and Safety
Use the correct vehicle connectors and ensure proper power requirements. A 10amp trailer wire or 15amp trailer wire may be necessary for different applications. Use a circuit breaker kit for the brake circuit and breakaway circuit to maintain safety.
Conclusion
Proper trailer plug wiring and understanding of trailer wiring colours are crucial for maintaining your trailer’s electrical functions. By following industrial standards and using the right connectors and wiring diagrams, you can ensure a safe and efficient towing experience.
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Disclaimer: The information provided in this blog is for general informational purposes only. While we strive to ensure the accuracy and reliability of the information we strongly advise that any electrical work or modifications be carried out by a licensed and qualified professional electrician. The content of this blog should not be considered as a substitute for professional advice or consultation. Any reliance you place on such information is strictly at your own risk.
