Have a 02 f150 with a 4 pin flat and need to convert to a 6 pin round trailer. Think I need to splice into brake wire before rear connnection to left of spare, yes?

 

Most trailers without electric brakes use the 4 pin flat connector. Since 1997 the trailer industry and truck industry has standardized and uses the 7 pin trailer connector for trailers that use electric brakes.

There are a major problem with the 6 pin connectors and it is two fold. First there are two different ways they are wired; and if you wired it different from the trailer, the brakes will be locked up when connected to the tow vehicle. Second, with a metal connector housing dirrect shorts are very common in the connector itself.

I highly recommend converting to seven pin/4 pin combo with a complete wiring harness all you wil have to do is plug it in and you will be done.

With that being done, I also recommend changing the trailer into the 20th century with a 7 pin.

Now, to answer your question. All of the wires should be there at the rear of the truck unless your wiring harness for your truck only had 4 wires just for the 4 pin flat. If so you will need an additional wiring harness with all 7 wires, and then connect the trailer wiring connector you choose. Most of the time all of the wires are in the harness even if only 4 are connected to a 4 flat.

 

http://www.etrailer.com/mm5/merchant...ategory_Code=A

This is the one I installed on my truck, and it took no more than 15 minutes to do, if you don't want to change your trailer connections, you can get an adapter like this one:
http://www.etrailer.com/mm5/merchant...ategory_Code=A

But, like Colorado Osprey said, the 6 pin round connectors have a different pinouts when it comes to the brake wire, and the adapter above is for the center pin is the brake

 

Thanks, but I am leaving tomorrow AM for CA and don't have time to upgrade the trailer harness to 7 pin. Just purchased it used, like new and am trying to get it registered before I leave. Have the 4 to 6 adapter already and mistakenly thought the brake lead was for lighting, not trailer e brakes, and was wondering if the brake lights are tied through the same lead. Hooked up the adapter to the 4 pin, and have running lights but no brake or signals, yet do have emergency flashers throught to trailer. Checked all fuses and grounds without resolution. Any more ideas?

 

Be careful. The 4 pin has no electric brake wiring. That requires an electric brake module in your cab ( lots of aftermarket available). Basically it uses inertia to determine how much power to send to the electric brakes. You cannot just use the brake light wire to power the e brakes. ( If you already know this, then I apologize ) Some times it is good to restate the obvious. Can never be too careful.

 

While you can get an adapter for a 4 pin to 6 pin and all the lights should work, except for the electric brakes themselves, but you should still have the brake LIGHT come on the trailer when the trucks brake is applied...

The connection point by the spare tire has the brake controller lead run up to that point.

What you need to do is get a 'factory' 7 pin to connect to the main harness by the spare tire and then get a 7 pin to 6 pin adapter to connect to the trailer. That way you will have the brake controller wire in place (assuming that the 6 pin is wired the same as the 7 pin adapter is...) then make sure you have the 30a brake controller fuse under the hood, get an actual brake controller to plug into the connector under the dash and you are good to go!

Don't think that you will have electric brakes just because you hook the trailer 'brake' wires together.... You need the 'controller' to activate the whole mess..

Good luck!

Mitch

 

Ended up being a combo of things. First, the 6 pin trailer end had been rewired to accomodate some other tow vehicle in the past. Rewired the connector to match the new adapter, and all was good.....until I removed the external ground wire I had attached from bumper to tongue to eliminate grounding as source during the rewire. Guess I was too careful when mounting the reciever and ball. Didn't scratch the powdercoating during the installation and my hitch wasn't grounded to the chassis.
Thanks for the leads folks.

 

I bout a 4 pin into 7 pin adapter. The same one from the above link. So my question is, would my truck have the wires to hook up the brake controler, reverse lights and aux power in the back? If not do I just need to run the two wires back, and tap into my reverse light wireing? I have an 01 scab 4x4 if it matters.

 

As of 1997 all these trucks are pre-wires unlike some other companies trucks like Dodge, Toyota, Nissan, Jeep, etc.

Your wires end in a wire connector next to the spare and you'll just need to unplug the harness with the 4 pin connector and plug in a new wiring harness with the new 7-way/4way combo or just the 7 pin. Then you will need to check your owners manual to see if your fuses/relays were installed for trailer charge and trailer electric brakes. If not they will need to be installed for all 7 pins to work correctly. A brake controller will also need to be installed in the truck and the female end of the wiring harness will be a 6 pin grey connector under the dash behind your OBDII plug. To install a brake controller you will need a wiring harness to plug into the existing harness in your truck and then to the new brake controller.

It's all pretty simple, just unplug and plug in...except be carefull with the brake controller harness, the colors in the wires may or may not match the brake controlller wire colors.

 

Ok I have the 7 pin adapter already installed hooked up to the factory 4 pin plug. So what wires do I need to splice at the connection by the spare tire? I only need to splice in the 3 wires to have a fully functional 7 pin connector.

 

The connector I was referring to does not need any splicing, it would have unplugged where your 4 pin plugs into the harness and plugged right in and all 7 wiress would be done.

There is 1 or 2 wire connectors at the plug in your harness where your 4 pin plugs into the main harness next to the spare. If you look at the wires that are not being used you'll see an Orange wire..that's your 12v+ and your see a Blue wire...that's the electic brake feed. The brown wire with the green trace is the reverse light.

I wouldn't cut into the factory main harnesss, that's why I recommended the factory combo that plugs right in. To use the one you bought, I would use a scotch lock to tap into the factory harness to prevent excessive damage to those wires.

Good Luck...............

 

Cool thanks. Yeah I needed a 7 pin quick, and only needed the trailer lights to work at the time, but would like to have the 7 pin fully functional.