Trailer running/tail lights not working!!

In a bind we used to put a jumper between the brown an black wires.
Folks need more info about your truck for other advise.

 

Times 2

 

Lol... I followed a truck for over 100 miles a couple of nights ago that had this same problem... Tried hollering at them over the CB, no response. Just so happens that they were also stopping in Walcott, IA so I follwed them into the truck stop and told the driver about the problem before I went to park for the night.


Test the pins where the pigtail connects to truck. If you have power there on the pin that goes to brown wire in pigtail, then all you need to do is buy a new pigtail. If no power the issue is in the truck. Id bet that the brown wire is broken inside the pigtail.

 

Several times I've needed a new one.

 

You need to buy a test light and start poking around. Check the plug on the truck. Could have a broken wire behind the plug

 

Had that problem recently. No power from the truck for clearance lights, markers on trailer.
Fuse was blown, and kept blowing. So I knew I had a short.
Took me about two hours to find it was the lisence plate light assembly that had the short. Easy to fix at least.