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I have running lights but no brake lights nor turn signals on my trailer. I have a 4 prong flat on my truck. Where there is a ground prong and 4 female plugs. However the boat trailer has the ground prong and only three male prongs. Does anybody have a solution to this?? I didn't know if I needed to put a 3 prong on my truck or what. All info is greatly appreciated!!!
go to a U-Haul shop and buy an adapter. It'll have instructions but they should be able to show you while your there
There are adapters available for any combo of wiring harnesses. I've seen them at TSC and auto part stores but I would recommend stopping by your local marine shop first. They should have what you need or be able to tell you where to get it.
[QUOTE=Simonlawnservice;516575]I have running lights but no brake lights nor turn signals on my trailer. I have a 4 prong flat on my truck. Where there is a ground prong and 4 female plugs. However the boat trailer has the ground prong and only three male prongs. Does anybody have a solution to this?? I didn't know if I needed to put a 3 prong on my truck or what. All info is greatly appreciated!!![/QUOTE]
It's a ground issue. The three wires on the trailer are running the lights, brake lights, and the turn signals. The wire missing is the ground wire. Older trailers have this set up, and use the ball on the truck for grounding. Buy a new 4 wire connector for the trailer side and install it, grounding out the white wire to the trailer. This will fix your problem, I know because I've had the same issue.
[QUOTE=Simonlawnservice;516575]I have running lights but no brake lights nor turn signals on my trailer. I have a 4 prong flat on my truck. Where there is a ground prong and 4 female plugs. However the boat trailer has the ground prong and only three male prongs. Does anybody have a solution to this?? I didn't know if I needed to put a 3 prong on my truck or what. All info is greatly appreciated!!![/QUOTE]
I think you will find the truck is setup for a trailer with surge brakes, the extra wire is the backup light circuit that goes to the release solenoid for the brakes when backing up. You can buy an adapter to hook-up one to the other. Auto Zone Walmart etc. should have this.
so apparently in 98 ford forgot to put in the owners manual that there is a small 3rd fuse panel that holds a 5a and 20 amp fuse. the 20a runs the brake and turn signals for the trailer. of course once i found it it was blown and i replaced it and all works well. just a little heads up for anybody that has a f150