2008 F150 trailer tail light terminal - no power

[tie_one_on]

2008 F150 4X4
Hooked up the trailer. Had a problem with trailer wires. Fixed trailer wires. Trailer is okay now.
My turn signals and brake lights work but the tail lights don't (including the marker lights)

So I checked my factory plug on the truck and I have power to the yellow and green terminals (these control the turn signals and brake lights).
I don't have power to the brown terminal for the tail lights. Tail lights on the truck work fine.
What could be the problem? How do I determine it? Most important... how do I fix it?
Thanks.

 

[mudslinging79]

Re: 2008 F150 trailer tail light terminal - no power

check the wiring where it goes into the trailer plug, may have a break before the plug thats afecting the no power situation.test with a test light, to fix, splice and shrink wrap the splice

 

[dockwrecker]

Re: 2008 F150 trailer tail light terminal - no power

I've read here that there are two different fuse locations for the taillights on Fords, one under dash and a seperate one under the hood specifically for trailer wiring. Consult thee thy owner's manual. Or delve into the Iboat archive of trailers for further info. This has come up before. Good luck.

 

[Splat]

Re: 2008 F150 trailer tail light terminal - no power

My dads Ford has a "power center" under the hood, all the trailer wiring is fused in this box. I would check that first.

Bill

 

[Tim Wagner]

Re: 2008 F150 trailer tail light terminal - no power

I agree, there is a separate fuse for the trailer harness.
Been there done that!!

 

[Gary H NC]

Re: 2008 F150 trailer tail light terminal - no power

There should be a relay in the box under the hood and one of the relays marked trailer running lights.
Also there should be one marked spare.Most trucks have these.
You can try switching the trailer relay with the spare and see if that works.
Those relays should reset after they cool down but it may just have went bad.

 

[dvandsm64]

Re: 2008 F150 trailer tail light terminal - no power

if not fuses and/or relays it has to be a bad wire between the plug and where it hooks into trucks wiring.

 

[DJ]

Re: 2008 F150 trailer tail light terminal - no power

My dads Ford has a "power center" under the hood, all the trailer wiring is fused in this box. I would check that first.

Bill

Yes, check the power distribution box under the hood. Also make sure ALL of the brake lights work, including the one on top of the cab.

 

[BuzzStPoint]

Re: 2008 F150 trailer tail light terminal - no power

Time to break out the multimeter.

Probe the plug on the truck end to see if you have power. At every junction or plug, Probe again till you see power.

 

[RogersJetboat454]

Re: 2008 F150 trailer tail light terminal - no power

I would check your fuses first. If none are blown then just out of curiosity, how many miles are on it? Is it a factory tow package? A 2008 truck should be still within its warranty as long as you haven't exceeded the mileage.

As long as you haven't done anything to damage the wiring, you shouldn't waste your time and money fooling with anything more than a blown fuse when it could be repaired under warranty.