How to Wire a 4 Pole to 7 Pole Adapter
Question:
I am having trouble figuring out what i do with the extra blue black and yellow wires?? i have the ground connected but still no lights on the trailer? help please!
asked by: Deirdre D
Expert Reply:
We need to figure out why the trailer lights are not working. Use a circuit tester on your 4-way flat that you plugged into the back of the 4 to 7 pole adapter and test each function to make sure they are working correctly. If your 4-way is working properly, then you can plug it back in and test the corresponding poles inside the 7-way connector to be sure the adapter is working properly. If you need a circuit tester, we have part # PTW2993.
Next, you would have to plug in the trailer and make sure it is grounded. Also, check the brake, turn and taillights on the trailer. If the vehicle side is functioning correctly, the trailer side should work, or you have a problem there. The black, blue and yellow wires are not related to the taillights and are for other functions. The black wire is for 12-volt power from the battery. The blue wire is for trailer brakes from the brake controller, if you have one. The yellow wire (orange) is for auxiliary power. These wires do not need to be hooked up for the taillights to work. Look at our wiring page (see link below) and it will help you through the process.
Products Referenced in This Question
Product Page this Question was Asked From
Adapter 4 Pole to 7 Pole Vehicle End Trailer Connector
- Trailer Wiring
- Wiring Adapters
- Single-Function Adapter
- 0 - 5 Feet Long
- 4 Flat
- Plug and Lead
- 7 Round - Blade
- Tow Ready
more information >
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