trailer lights

[flonly]

I ran last night and i pull two trailers.I went over RR xing on my return trip and all my trailer lights went out.When they went out the flasher indicator lights on dash would stay lit solid from then on the rest of my trip home about hour and 45 min it keep happening sometimes a secnd or two to 10 seconds.Not sure if truck or trailers.Any thoughts from anyone?

[Rawze]

pigtail getting weak and shorting out?

[flonly]

tried wiggling it and made no difference .when i stopped in turn lane they came on and when messig with pigtail i could not make them go out

[Waterloo]

Sounds like a ground issue. When this happens to me, if I cannot visually see something, I run both the truck and trailer into a shop with one of those trailer electrical diagnostic tools. It could be anywhere in either your truck or trailer(s).

Also, many trucks have a grounding strap from the tractor frame rail to the fifth wheel. If that grounding strap is broken, or lose, it will give you issues like you are having. I had this happen on a new Pete once, drove us nuts for a week or two. Trailer shop figured it out in around ten minutes. The fifth wheel grounding strap was still connected, but not making good contact. The reason I like to take both units in when issues like this happen. A good trailer shop has the diagnostic tools to figure this stuff out, beats crawling around under the truck and trailer chasing wiring for hours on end.

[stevesparts]

Im with waterloo on this on.. had the same thing with one of my KW's it would have all sorts of trl. light problems,drove me nut's till i went through and ran grounding line on every thing. was pulling tanker then and would park at a place to unload and nothing would work on the trl at all. but try grounding the fifth wheel to see if that fix's the problem.

[flonly]

thanks .I ran again different trailers and same thing.Its real incosistant one minute you hit a rough spot in the road they go out for 3 seconds then next time you are on smooth surface and they will do the same thing and everytime they go out flasher indicator stays on.Then may not do it again for 3 hours. I do have one solution 5 gls of gas and a match

[in2trux]

Instead of a grounding issue it sounds more like a hot short to ground in the turn signal circuit if the dash indicator is staying lit. Check the breaker to see if its overheating. Look for rubbed bare wires. It's doing the same thing with different trailers then it's on the tractor.
I would start with the tractor taillights, turn signals since they take such a beating from road debris and salt.

[flonly]

Thanks everyone I think it was the female plug on the back of truck.I bought a new pigtail and when i went in Friday night i tried to unplug the old one and it was stuck and didnt want to come out I pulled harder and it pulled the ground pin from the truck plug.So I replaced it this morning and hooked a trailer up.All the lights work.We will see Monday nght if it rears its ugly head.