j.kenzie@sbcglobal.net

Hi guys,
I recently noticed low grade static when I step on the brake pedal. I had disconnected the battery so I was between stations. When there is music, I don't hear it much, but it's there. I could go back to incandescents just to be sure of the source, but is there a way to keep the LED's with some wiring trick?
Thanks,
Dave

Speedtoys

Seeing a lot of this on the Google .

https://betterautomotivelighting.com...ed-headlights/

Randy V

Did you install the resistor kit when you did the LEDs?

If not you will get a tail lamp warning.

j.kenzie@sbcglobal.net

Hi Randy,
I used LED's in the main rear brake lights and regular incandescent in the center mount brake light. No warning light. I didn't use any resistors. I do have static.
How do resistors mount?
Thanks,
Dave

Speedtoys

The resistor is just a parallel resistor to draw more current to avoid a dash warning light.

Has nothing to do with the static.

NelaK

Possibly a ground loop. Car audio systems are especially vulnerable to them.

I'm guessing you have a head unit of some sort, and a separate amplifier? They are connected to each other via an audio cable and both are also separately connected to ground. That audio cable creates a secondary path to ground for each of the devices.

Other loops can also exist in your car. Any two or more devices with a data cable between them. As long as you have grounds with different potentials, a bit of noise will be created and the device designed to amplify electrical signals will naturally do it's thing.

Hunting and addressing every device will be a pain so you can purchase a ground loop isolator.

The other source of the noise could be the LED controller. They control their brightness by rapidly switching the LED on and off. This also creates noise in the system. Especially if the controller isn't receiving as much voltage or current as it likes because of a bad connection.

Tldr; old cables, and bad grounds cause weird issues.

Note: This is all assuming Speedtoys suggestion doesn't resolve it

j.kenzie@sbcglobal.net

Thanks guys. I have a bunch of ferrite core RF filters somewhere. I will give it a try. I may revert to incandescent also. No separate amplifier, just a after-market head unit. I will check connections and may add an extra ground cable.
Thanks again,
Dave

Speedtoys

I have it too, its not a loop. It make it seem like your station is 50mi farther away when you turn on the lights. Its plain old RF white noise. Not the rational speed whining of the alternator...a ground loop.

j.kenzie@sbcglobal.net

I couldn't find the ferrite cores that I have somewhere, so I put in some incandescents and the static is gone. Unfortunately, I cracked my tail light lens pulling it. I ordered a used one and fixed this one.
Thanks for the help,
Dave