02 Tundra Harness HELP

[rchaney99]

Hi,

I have a 2002 Toyota Tundra V8 Access Cab. I believe it was factory installed with a tow package. I am looking to hook electronic trailer brakes up to it, but right now I only have the 4 pin on the back of the truck for lights. I crawled under the truck and found a wire harness plugged into a terminator on the frame. It has a blue wire for the brakes I believe. See picture in link below. Does anymore know if this harness will support electronic brakes? If so, do you know the part number or where I can order one? I need a 7pin harness.

I hate to install all new wires, or splice the ones that are there.

Also - I tried finding the harness upfront under the dsha or a brake unit, but have no idea what I am looking for. Any suggestions there as well?

PICTURE: http://www.lmsed.org/harness 1.jpg

Thanks for the help.

Ryan

[ma717mgte]

i think 02 had the harness for the trailer brakes in the left foot well but i cant remember, that draw tight is aftermarket, in my 00 i had a hoppy unit for a 4pin plug, for my 7pin i got mine from Advance auto. but autozone or tractor supply also has them. i got a plug that has both 4 & 7 for your trailer, and the Truck side has a 4 pin from your existing harness, i dont see the "blue" wire you speak of. but i did run my own to the cab and to the prodigy p3 i purchased, wiring it up is easy. if you was closer i would do it for you.

i got pix, but not uploaded yet.

[RockyMtnRay]

Originally Posted by rchaney99

Hi,

I have a 2002 Toyota Tundra V8 Access Cab. I believe it was factory installed with a tow package. I am looking to hook electronic trailer brakes up to it, but right now I only have the 4 pin on the back of the truck for lights. I crawled under the truck and found a wire harness plugged into a terminator on the frame. It has a blue wire for the brakes I believe. See picture in link below. Does anymore know if this harness will support electronic brakes? If so, do you know the part number or where I can order one? I need a 7pin harness.

I hate to install all new wires, or splice the ones that are there.

Also - I tried finding the harness upfront under the dsha or a brake unit, but have no idea what I am looking for. Any suggestions there as well?

PICTURE: http://www.lmsed.org/harness 1.jpg

Thanks for the help.

Ryan

Hate to tell ya' but you're going to have to do some wiring. Toyota didn't include factory wiring for a brake controller in the towing packages until the '03 Tundras.

Which means you will indeed have to run a wire from the battery to the controller, a wire from the controller to ground, a wire from the controller to the brake switch, and a wire (which is typically blue) from the controller to the back of the truck (where it will connect to a pigtail on a 4 into 7 adaptor.

Your pic appears to show a 3 way converter (separate turn and brake plus taillights) into a 2 way (combined turn & brake plus taillights). Your truck uses a 3 way scheme, most trailers use a two way scheme. Whoever had your truck got an aftermarket converter instead of the Toyota converter. While it does convert your truck's turn signals/brake light/taillight into a 4 wire system for the trailer, it will not do anything for you with regards to trailer braking

[rchaney99]

Thanks for the help guys. That black box is seperate from the adapter plug you see in the picture. I just wanted to include it... The plug to the right of the black box actually connects to a plastic piece on the frame. Which I am guessing is to keep dirt out. This plug has a blue wire running into it along with the rest you see. What could this plug be for if not trailer breaks?

Here is a link to a pic of the wires including a blue wire.
http://www.lmsed.org/harness 2.jpg

[RockyMtnRay]

Originally Posted by rchaney99

Thanks for the help guys. That black box is seperate from the adapter plug you see in the picture. I just wanted to include it... The plug to the right of the black box actually connects to a plastic piece on the frame. Which I am guessing is to keep dirt out. This plug has a blue wire running into it along with the rest you see. What could this plug be for if not trailer breaks?

Here is a link to a pic of the wires including a blue wire.
http://www.lmsed.org/harness 2.jpg

Assuming that plug was part of the factory wiring harness, you'll have to get a wiring diagram for '02s to determine it's purpose. What I can guarantee it is NOT is a plug for trailer brakes because the '02 Tundra factory tow package simply did not include trailer brake wiring. No ifs, no buts, just plain not included.