Troubleshooting Trailer Lights With 3 Wires Connection to 4-Wire Trailer Wiring Harness
Question:
My plug has 4 wires and my trailer lights only have 3 out of each side. How do I connect?
asked by: Bill
Expert Reply:
Your plug wires will have running light, stop and turn light for each side and then a ground connection. Your trailer lights with 3 wires will either have separate stop and turn lights or a separate ground wire instead of using the mounting hardware as ground. You will want to use a battery and jump wire to test your trailer light wiring unless it is obvious based on the light bulb sockets. If the wiring is connected, you can use a circuit tester like # PTW2993 to probe the insulation on the wire to test function. I've attached an article to assist.
If you have separate stop and turn functions on your trailer, then you can use wire converter # 118158 to separate the turn signal from the brake light function.
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Products Referenced in This Question
Vehicle to Vehicle Tail Light Converter
- Accessories and Parts
- Trailer Wiring
- Mounting Hardware
- Brackets
- 7 Round
- 7 Round
- Tow Ready
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Product Page this Question was Asked From
Pollak Black Plastic, 7-Pole, RV-Style Trailer Connector - Trailer End
- Trailer Wiring
- Trailer Connectors
- Trailer End Connector
- Plug Only
- 7 Round - Blade
- Pollak
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