The red wire coming out of the 7 way is probably the 12v feed when the truck is in acc / or running. I added a switch box to my Puma Step Pole that uses the 7 way 12v feed to power 2 floodlights on the pole. One points down the boat and the other point down towards the hitch for hooking up in the dark. I added a Milwaukee 12v rechargeable tool battery inside the box to power the lights when the truck is not connected. The backup solenoid should be off of the blue wire as it uses the backup light circuit of the tow vehicle to activate.
I was replacing my 7 to 5 coiled adapter for my trailer lights today when I noticed a small red wire in the trailer tongue near the hinge joint. It appears it has been broken for a while. I have not noticed anything not working on my trailer. Does anyone know the purpose of this red wire? I went ahead and spliced it back together.... see pictures below.
Any insight on the wire is greatly appreciated....
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