09 Expy Trailer Brake light issues. . .

[max78]

Hi all I'm in need of some help.

I have no power to the trailer brake light specifically. I have running lights, just no brake lights or turn signal (same wire). I tested the wire before it enters the plug so its not a plug issue.

All the fuses under the box and in the kick panel are good.
The relays are working.

I suspect something with that wire has gone wrong, but I cant trace it from the front all the way to the back. is there a connection or specific area I should check for this thing?

Any help would be greatly appreciated!

 

[Plati]

You said "wire" as in one wire, but you meant both wires, right?

Do you have both a 4 pin and a 7 pin connector?
Problems with both?

I used to carry a 7 pin to 4 pin adapter to use if my 4 pin connector failed.

 

[07navi]

Hi all I'm in need of some help.

I have no power to the trailer brake light specifically. I have running lights, just no brake lights or turn signal (same wire). I tested the wire before it enters the plug so its not a plug issue.

All the fuses under the box and in the kick panel are good.
The relays are working.

I suspect something with that wire has gone wrong, but I cant trace it from the front all the way to the back. is there a connection or specific area I should check for this thing?

Any help would be greatly appreciated!

Year? Model?

 

[max78]

Its a 2009 Expedition EL.

It has a uhaul brake controler installed. Plug is a 4 pin, and a 7 pin. However I have removed that box from the equasion by going directly to the factory 4 flat plug under the truck.

I get no power at the wires (green and yellow) before the factory plug for brakes, or turn signals.

I do have power for running lights (brown).

I chased the wire as far as i could today, just infront of the rear spare where it splits off. All factory not tampered or spliced.

 

[07navi]

Its a 2009 Expedition EL.

It has a uhaul brake controler installed. Plug is a 4 pin, and a 7 pin. However I have removed that box from the equasion by going directly to the factory 4 flat plug under the truck.

I get no power at the wires (green and yellow) before the factory plug for brakes, or turn signals.

I do have power for running lights (brown).

I chased the wire as far as i could today, just infront of the rear spare where it splits off. All factory not tampered or spliced.

Sounds like you have the tow package with about 11 wires+- , just keep checking them with a test light. This has always been my biggest towing fear but it was always hooked up wrong or a fuse. There are a lot of fuses under the hood and side panel. Look at every fuse and relay that even distantly resembles towing.

 

[max78]

Sounds like you have the tow package with about 11 wires+- , just keep checking them with a test light. This has always been my biggest towing fear but it was always hooked up wrong or a fuse. There are a lot of fuses under the hood and side panel. Look at every fuse and relay that even distantly resembles towing.

Thanks i will look at all the fuses again. Its been working flawlessly for the entire time i have had the truck and use it quite often. This started just recently and its driving me nuts.

 

[Earthmover]

Make sure the trailer wiring is good may not be the truck. Hook to another truck ?

 

[07navi]

Make sure the trailer wiring is good may not be the truck. Hook to another truck ?

He has been testing all the wires already.

 

[chuck s]

All Ford trailer wiring comes thru a relay as well as fuse. Could be there as well. Not sure what works with the ignition off either.

-- Chuck