boat trailer lights not working

[styx]

My boat trailer lights do not light up when they are hooked up to my truck. they work when I signal a turn or when i step on the brakes. Any ideas on what is wrong?
thanks

[BrianP]

Four out of five times it is a problem with your ground wire (white). Test for continuity with an ohm meter from your plug on the truck to the frame. You should have zero or numbers in the hundredths. Then check for 12+ at the brown wire with the park lights on, left signal at the yellow, and right signal at the green wire. Yellow and green together make your brake lights. A bad connection at the rear of the trailer bulbs also can give you false readings.

[hitthebricks]

your running lights may be burned out! Try turning your flashers on and check what lights actually lightup. Or maybe just spray the connections with WD40 to clean the contacts( advice from handy hitch on hwy 36) these guys actually redid the wiring late on friday for 20 bucks. What a bargan! and saved me a ton of guess work. Good luck HTB

[Trailblazin]

I had the same problem and while it could be the ground, my guess is a blown fuse in your truck. Those will go out.

[Twitter]

styx,
It sounds like the fuse is blown. Which means there's probably a short somewhere.
On Fords and Mopars, there's a fuse UNDER THE HOOD for the running/tail lights.
It's not in the normal fuse panel under the dash. Pull your owners manual out and find the fuse box under the hood. The manual will tell you which fuse it is.
I've seen lots of guys spend hours trying to find this same "wiring problem" when it was just a blown fuse. AGAIN, the fuse probably blew due to a short somewhere. If the fuse continues to blow after replaceing it, you need to isolate the short.
Good Luck !
Let us know the outcome.
Twitter

[Big Northern]

I had a similar problem last week. It was a bad fuse. In my case it was an in-line fuse under the back bumper, just back from the plug on my Nissan Pathfinder.

[rms]

Get a tester, turn on your running lights, and check all the conections on the plug to see if you have power coming from the car side of the plug. If so, start from the trailer plug and work your way back until you find where the power ends. (Do this after checking fuses and light bulbs.)

[This message has been edited by rms (edited 07-27-2004).]