Replacement 5-Flat Trailer Harness
Question:
I have a 2004 Four Winns boat trailer with surge brakes. The tongue has a wiring harness I estimate 5-7 ft long with flat four prongs on one end 3 female, 1 male that connects at the point the wishbone meets, and a flat five prong 4 male, 1female that has the extra blue wire connected to the vehicle. The blue wire has been cut flush with the entry point on the flat connector so it cannot be spliced. Do you sell a replacement for this wiring harness? The closest I could find is the Yakima one but that is a four prong on both ends.
asked by: Chris H
Expert Reply:
Thank you for the photo; from that and your description it sounds like all you need is a replacement 5-Flat for your trailer and I recommend the 5-Flat Trailer End 48" Harness # 20017.
What you can do is simply cut off the 5-flat that is on your boat trailer and use the quick splices that come with the # 20017 to splice into those wires. I have added a link to a video which shows an install of a 5-flat on a boat trailer, as well as a link to a help article on trailer wiring which I strongly recommend checking out.

Products Referenced in This Question
5-Flat Trailer End 48" Harness
- Trailer Wiring
- Trailer Connectors
- Trailer End Connector
- 0 - 5 Feet Long
- Plug and Lead
- 5 Flat
- Draw-Tite
more information >
Product Page this Question was Asked From
Replacement Tongue Wiring Harness for Yakima Rack and Roll Trailers
- Accessories and Parts
- Trailers
- Watersport Carriers
- Sports Trailer Parts
- Watersport Trailer Parts
- Wiring
- Rack and Roll
- Yakima
more information >
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