LED light bar issues
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Junior Member
Joined: Oct 2025
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LED light bar issues
Hey guys, 2018 F150 here. I wired a light bar to relay with high beams as switch. Light bar comes on, but relay buzzes like an angry hornet. I have tried three different relays, and they all buzz. Whats going on?
Senior Member
Joined: Jul 2018
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From: My House
Welcome to the forum.
PWM, pulse width modulation. The relay is being turned on and off so fast, it buzzes. Does it buzz with the truck off? Look into adding a capacitor to the relay that will be a buffer when the power to the relay is turned off. Should eliminate the buzzing like this video here....
PWM, pulse width modulation. The relay is being turned on and off so fast, it buzzes. Does it buzz with the truck off? Look into adding a capacitor to the relay that will be a buffer when the power to the relay is turned off. Should eliminate the buzzing like this video here....
