Troubleshooting Trailer Wiring that Shorts Out Truck's Trailer Running Light Circuit

Question:

6 pin round into 7blade round. Trailer Blows fuse on truck instantly when plugged in. 2015 Ford F-250 has 30A fuse for trailer running lights. Brake and turn lights work. Trailer has wire Junction block Cleaned the 6 pin round with contact cleaner replaced the 6to 7 pin connector. Wire is in loom No visible pinches .

asked by: Darryl

Expert Reply:

Since the trailer running lights fuse is blowing on your truck when plugged into your trailer and the wiring at the junction box looks clean as well as the pins of the connector being clean I would recommend going over the wiring of that circuit from the box back to the taillight assemblies. Most likely you'll find a portion of the wiring that is cut with exposed wire that is touching the metal frame of the trailer which is causing the short.

I also attached a help article on troubleshooting trailer wiring for you to check out as well.

expert reply by: Jameson C