Troubleshooting Trailer that Work Differently When Headlights are on and Off
Question:
Hi I was working on my gooseneck horse trailer. Older metal model. When i got the trailer the running light on the breaks worked but none of the other running lights. Changed the back two side marker lights everything works perfect except the front 2 running lights. Change them out and now running lights only work when brake is pressed and blink with signal. There was only one wire in the front i messed with. Any idea what coulf have happened?
asked by: Kelli B
Expert Reply:
Sounds like a ground issue. Anytime we see lights not working, or working strangely and the headlights are a variable for when they work or not the issue is always an insufficient ground. If you can run an additional ground wire from the lights back to the main ground wire of the trailer harness this will fix the issue you described.
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