Trailer harness question

[rolfsent]

I just purchased a 2006 Yamaha sx210 jet boat. The trailer for the boat has a 5 pin connection. My 1999 Denali only has a 4 pin connection. How do I convert my 4 pin into a 5 pin?

 

[the big blue bus]

what type of plug do you have currently? 4 flat? you could cut that off and solder on the new 5 plug one and run the 5th wire to the reverse lights. there should be a stock harness under the truck. there is on my 95 all 7 wires just havent put a plug on yet. going to do a 4/7 one. the wires are taped up by the spare tire crossmember and if you have a pre installed plug look under there for the remaining wires. the reverse lights wire is a light green(well on mine anyways)

 

[rolfsent]

It is currently a 4 flat. I'll check to see if I have the other wires. Where do I get the new 5 pin connection?

 

[the big blue bus]

which type is on the trailer? any like auto store/walmart/hitch place you can get em from

 

[rolfsent]

The trailer has a 5 flat

 

[SunlitComet]

the fifth wire is most likely the reverse light circuit when going from 4 to 5 wire.

 

[JubjubW]

Or you could just buy an adapter, my father in law has one since his came with a 5 pin on his truck, but all his trailers are 4 pin and don't fit

 

[rolfsent]

I bought a 5 pin harness to splice into the existing wires. The fifth pin is to send a signal to the trailer that it's in reverse to keep the brakes from kicking on. I assume I can just run this to my tail light and tie it into my reverse wire. Does anyone know how to do this?

 

[SunlitComet]

never heard of that before.

 

[rolfsent]

The boat trailer has surge brakes. the brakes are pressure activated by the weight of the boat trailer being pushed forward towards the truck. The 5th pin is tied into the reverse so that when you back up the trailer it does not activate the brakes because of the pressure forcing the trailer towards the truck.