Brake contoller and 4 to 7 pin

I have a 2007 dcsb SR5 4x4 that has a 4 pin trailer connection. I have researched quite a bit and am still unclear on some things.

First I have a Tek P3 with the Tacoma wiring. I found the receptical plug in the truck cab.

I believe I will have to run a wire back to the rear for the 12v charging portion of the 7pin plug and I can use the 4 wires from the 4 pin harness. Where I am stumbling is the trailer brake wire. I believe one of the wires in the can harness would run to the rear but I am unsure of where? Any help or direction to a thread would be great. Thanks.

 

No answer to above question but I have one of my own : I just wired my boat trailer with LED tail lights and I have some issues. is a 4 wire harness (wht,, brn, yel, green). My 2001 Tacoma has 2 connectors, the 7 pin round and a 4 pin flat.

1) When I hook up to the 7 pin round connector using an adaptor, the running lights and the turn signals work fine, but no brake lights.
2) When I hook up to the 4 pin connector, the running lights and brake lights work, but no turn signals.

Anyone have this issue ?

 

See if what you need is here
https://www.tacomaworld.com/threads/factory-7pin-trailer-harness-installation.390335/

 

Here's some pinouts of the connectors. Get ahold of a multi-meter and see what you have wired up.
https://www.etrailer.com/faq-wiring.aspx

 

Thanks for the response sandman. I figured it out. The factory under the dash plug has the wire that would run to the back for the brake controller but it stops at the next connector and doesn't run back to the rear of the truck so I just need to run that wire back.


Multi meter is defiantly the way to go to see if there is voltage to the connector. My guess would be corrosion on wires or connectors.

 

Yea since my truck didn't have the tow package, I am adding it in manually. You can get the exact pins for the connector and run your own wire.

 

Thanks Sandman but I have the trailer wired correctly. The problem is in the connector on the truck. The connector is wired up for a 4 pin configuration (grn, yel, brn, wht) and I have good grounds. Rt and lt turn signals work, running lights work, but not the brake lites. These would be the same wires as the turn signals. Where would I find the 5 to 4 wire converter ? Does anyone know ?

 

Sandman, do you have a source for the pins? I’m currently trying to do a controller install without splicing and using factory connections.

 

I think I got them from Ballenger motorsports