Where Does Interior Lighting Circuit Come from on Trailer 7-Way
Question:
I recently purchased a 7 pin plug for my horse trailer which had a 6 pin plug, Since my truck has a 7 pin connector, I need the two to match. This is my problem, there is a separate circuit to power several interior lights in the trailer. It is on a brown wire. Can you tell me how I should connect that additional wire to the 7 pin plug. It also seems that it will have to attach to one of the pins with constant power. For example, it could possibly connect to the same pin as do the running lights... even though the lights on the truck will have to be on to power the interior trailer lights., ??? Also, my horse trailer has electric trailer brakes, but there was only 6 wires in the old plug, and none were blue. I cannot figure out what wire powers the electric trailer brakes. Any help that you can provide would be greatly appreciated.
asked by: Mark P
Expert Reply:
The pin in the 1:00 position of a 7-way is the 12 volt accessory circuit and the one to use for powering trailer interior lights.
A lot of times trailers don't use standard wire colors so you will need to trace the wires back to where they terminate on the trailer to be able to tell their function and then wire by function according to the diagram I attached.
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Product Page this Question was Asked From
Adapter 4-Pole to 7-Pole and 4-Pole
- Trailer Wiring
- Wiring Adapters
- Multi-Function Adapter
- 4 Flat
- Plug and Lead
- 4 Flat
- 7 Round - Blade
- Hopkins
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