LED Trailer Lights Are Only Flickering After Installing Trailer Towing Harness
Updated 04/16/2026 | Published 04/12/2026
Question:
This installed easily but when I test on my trailer with LED lights the lights only dimly flicker. Could this be a grounding problem? Software? Thanks in advance
asked by: Matt
Expert Reply:
Welcome back, Matt!
What you are experiencing definitely sounds like a grounding issue. Most likely on the vehicle, but it wouldn't hurt to double check the trailer as well.
Make sure all your grounds are on a good clean metal source that is not aluminum (commonly missed these days as there is a lot of aluminum in vehicles now) and they are not stacked on other grounds. This can be a common practice, but I always have better luck when each ground has its own location.
Since this is separate from the vehicles computer, it shouldn't be a software issue. Make sure that fuse inline with the battery is also in good condition and fully seated as well. It wouldn't hurt to make sure all the connections are completely snapped together.
Let me know if any of that helps. What kind of trailer are you towing?
Product Page this Question was Asked From
Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
- Custom Fit Vehicle Wiring
- Trailer Hitch Wiring
- Vehicle End Connector
- Powered Converter
- No Tow Package
- 4 Flat
- Plug and Lead
- Plug-In
- Hidden
- CURT
more information >
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Matt
4/15/2026
It was indeed the ground. Now that the ground is properly hooked up everything is working great. Thanks for your quick and on-point reply. I remain an e-trailer fan! I'm just pulling a utility trailer.