Troubleshooting a 2025 Chevy Trailblazer With Dim Headlights After Using Brake Buddy 3
Updated 12/15/2025 | Published 11/15/2024
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Question:
I have a 2025 Chevy Trailblazer LT. Tow bar is set up and works great, brake buddy 3 is functioning perfectly, I had the wiring harness installed for the variable incandescent lights and things go haywire. When I have the negative terminal disconnected as per Chevy the lights are a misfire. Sometimes they work but not as bright as they should, if the headlights are on nothing else is working, I am at a loss at this point if there is something that got connected incorrectly or what. Anyone successfully install this on a newer trailblazer?
asked by: Carrie
Expert Reply:
Carrie, it sounds like there may be a power supply issue or a bad ground in the wiring harness. I'd suggest checking your grounds and make sure they are not loose or damaged. If they are, then I'd start there and fix those first before moving onto other troubleshooting.
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Roadmaster Smart Diode Kit for Variable Voltage Incandescent Tail Lights
- Flat Tow Wiring Harness
- Splices into Vehicle Wiring
- Diode Kit
- Universal Fit
- Roadmaster
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Jerred H.
12/15/2025
Hey Carrie, did checking the grounds on your Trailblazer’s wiring harness clear up the lighting issue? Knowing what fixed it could really help others working with the same diode kit.