Help with new tow vehicle.

[SigSaurP229]

I have a 2005 Ford Expedition Eddie Bauer with the HD tow package 7 and 4 pin connectors.

I noticed I have absolutely no brake lights when I hook up my trailer. I do have Taillights when the Headlights are turned on. Brake lights are fine on the truck (except I noticed that the third brake light is out).

What is even weirder I have no hazard lights either (They both work fine on the truck) but when I turn on either turn signal both lights on the trailer blink however very dimly Volt meter reads about 8.6 on each when either turn signal is on.

I have been through the little fuses nothing is blown, I looked at the larger fuse number 106, it was actually missing in the box. It made no difference does anyone have any other ideas of where I should be looking. I have isolated the problem definetly to the truck not the trailer. Volt meter reads zero on the 4 pin plug when the brakes are pushed and reads the same 8.6 on both sides when either turn signal is on, but 0 when just the hazards are on.

 

[tpenfield]

Re: Help with new tow vehicle.

I would check to see if you are getting brake, turn signal, flasher voltage on pins 5 & 6 of the 7 pin connector of the vehicle. Those are left & right turn signal in the image below. Click thumbnail for larger version. That will tell you if the problem is at the 7 pin connector or at the 4 pin adapter . . .

 

[tpenfield]

Re: Help with new tow vehicle.

duplicate post (delete)

 

[SigSaurP229]

Re: Help with new tow vehicle.

Thanks for ur help i ended up changing both fuses in the truck and they work fine now

 

[Ming15237]

Re: Help with new tow vehicle.

We're the fuses blown?

 

[jkust]

Re: Help with new tow vehicle.

Betting you Ford is like my GM Suv's that have three separate fuses for the trailer lights. One of them is that square kind that is hard to get.

 

[haulnazz15]

Re: Help with new tow vehicle.

The 4-pin normally works fine, but the 7-pin requires a relay to be installed in the fuse box for the 7-pin to function properly. The usually included a package with the new vehicle which contained the relay and a electric trailer brake controller wiring harness.