Coverting 4 pin to 5 pin harness

[rednspeck]

OK guys I nned some help. I'm getting ready to buy a new boat and the trailer has surge brakes and has a 5 pin harness. Its my undertanding that the 5 pin harness has the extra pin for the reverse lights to deactivate the surge brakes.

What is the easiest way to convert my 2002 Tundra factory 4 pin harness to a 5 pin?

[tundrafly]

You will need a 4 to 5 pin converter that taps into your reverse lights. Probably cost you less than $10 and 10 minutes. Any auto parts store should carry it. Good luck with the boat!

[wolfie410]

Here are a couple for under $10.

http://www.etrailer.com/pc-A~47515.htm
http://www.etrailer.com/pc-A~20036.htm

[rednspeck]

Thanks for the help guys. Went to Advanced Auto Parts and got the converter. I was worried that tapping into the reverse lights would possibly damage the "computer", but from what I've read I believe and hope that this is only for electronic brakes and not surge brakes.

[No_Tundra]

I'm confused... So the blue wire from the trailer is for the electric brakes on the (boat) trailer, right? But we tap into our reverse light wire to go from a 4 pole to a 5 pole end harness?? What does the reverse light do for the brakes on the trailer?

[jmo]

Originally Posted by No_Tundra

I'm confused... So the blue wire from the trailer is for the electric brakes on the (boat) trailer, right? But we tap into our reverse light wire to go from a 4 pole to a 5 pole end harness?? What does the reverse light do for the brakes on the trailer?

Hi,

You need to tap into the reverse lights on the truck for boat trailers that have surge activated disk brakes since disk brakes work in both directions. Drum brakes only work going forward, hence when you back up they aren't grabbing and you don't need it.

Disk brakes set ups have what is called a reverse solenoid installed with the brake actuator - the blue wire on the trailer side connects to the solenoid which blocks the pressure from the actuator when backing up - assuming you wire it into your reverse lights on the trailer.

Note, its not uncommon for boat trailers with drum brakes to still have the 5 pin connector since disk brakes are usually an option. If you have drum brakes you can just connect the 4 pin truck side connector to the 5 pin trailer harness as the outer 5th pin is for the solenoid.

HTH's,

jmo