Troubleshooting Running Lights not Working on Trailer
Updated 03/30/2020 | Published 03/28/2020 >
Products Featured in This Question
Question:
I have a relatively new trailer and when ANY truck is connected to it, the running lights on trailer work for a short period of time, then blow that fuse in the truck. I think its grounding. There is a junction box on trailer hitch where breakaway battery is stored. There are three ground wires in there connected by a wire nut. One goes to the plug, one to the brake battery, and the third is attached to the frame. There is a bunch of insulation melted off the wires within an inch of the wire nut. My question is...is my grounding issue it that area, or is it still possible that it could be a bad ground at any of the lights which each have independent grounds mounted to the frame. Its a 7 pin connector in case it matters. Just trying not to do more than I have to : Thanks in advance.
asked by: John B
Expert Reply:
It sounds like your issue is definitely coming from a grounding issue. I would start by getting those wires cleaned up and re attached. I would suspect that there is part of that ground coming in contact with the running light circuit causing it to blow that fuse out. You can use LCD Digital Circuit Tester part # PTW2992 to find what wire is providing the running light signal on your trailer and inspect it and the ground to see where they are making contact. Or where they may be pinched together.
Product Page this Question was Asked From
LED Clearance or Side Marker Light w/ Reflector - Submersible - 4 Diode - Rectangle - Red Lens
- Trailer Lights
- Clearance Lights
- Rear Clearance
- Side Marker
- Rectangle
- Surface Mount
- Submersible Lights
- LED Light
- 6L x 2W Inch
- Red
- Optronics
more information >
Continue Researching
- Q&A: Replacing Peterson PM130 Incandescent Trailer Lights with LED Versions
- Q&A: Replacing Norcold N410 Mini RV Fridge With Everchill RV Mini Fridge
- Q&A: Replacement Wheels And Hubs For A Triton LTWCI Personal Watercraft Trailer
- Q&A: Replacement Grease Seal For AL-KO 568208
- Q&A: Replacement LED Marker/Clearance Lamps for Peterson PM130 on 1998 4Star Horse Trailer
- Q&A: Standard Color Code for Wiring Simple 4 Wire Trailer Lighting
- Q&A: Troubleshooting Dexter Electric Over Hydraulic Brake Actuator Pump that Runs But Brakes Do Not Work
- Article: How to Choose the Right Trailer Hitch Class
- Article: Trailer Wiring Diagrams
- Article: Trailer Lighting Requirements
- Article: Wiring Trailer Lights with a 7-Way Plug (It's Easier Than You Think)
- Article: How to Bleed Your Trailer Surge Brakes
- Article: Cleaning Your RV Gray Water Tank in 5 Easy Steps
- Article: How to Dump Black and Gray RV Waste Tanks

