Troubleshooting A Buzzing Sound From A Tail Light Converter

Question:

I bought a used enclosed car trailer it has 3 taillights on each side 1 is turn 1 is brake and 1 is backup they are led. When i plug trailer into my 2022 GMC pickup the converter 118158 on the trailer buzzes when brakes are applied or emergency flashers are applied also the trailer has no brakes. Could the converter be bad? i know the person i bought trailer from pulled it with a 2015 truck. Thanks for any help

asked by: Jeff B

Expert Reply:

Typically if a Tail Light Converter, like your # 118158 is buzzing it's either just normal for that particular unit and is just the sound of the components inside of the unit being energized and vibrating inside the converter or the it's an indication that there's not enough power being drawn through the circuits. The lack of power being drawn through the circuits can typically be resolved by installing some load resistors like # DI34ZR. If the lights aren't dim when you press down the brake pedal then I'd assume this isn't the case for your specific situation but you could test the trailer with other vehicles to see if we can narrow down if it's the truck or converter itself.

We've also seen cases where the ground connection is loose or corroded and can cause issues like the buzzing noise you've been experiencing.

expert reply by: Kevin C