Interference from brake lights, signals, and rear defroster, Please Help!

[tommy234]

After installing a 4 Channel amp I'm getting a humming through all speakers.

It happens when I press the brake pedal or have my signal on and is much louder when I'm doing both at the same time. I also get a pop when turning on the rear defroster.

It gets louder the higher I set my gains.

I installed a noise filter which did absolutely nothing.

I am wondering what steps can be taken to try and narrow down what is causing this problem.

Any advice would be greatly appreciated

 

[viwil]

Have you checked the grounds? Maybe adding an additional ground wire from the Battery to the frame of the car? Or regrounding the Amp grinding the ground point to bare metal.

 

[viwil]

I personally have never found a filter to work, I tried on my '04 golf

 

[tommy234]

I was thinking of doing a big three upgrade when it gets a little warmer out. Also checking the ground on the HU. Ya I figured the filter wouldn't work either but it was worth a shot

 

[evilmonstertruk]

Ground or RCAs.

Sent from my LG-H910 using Tapatalk

 

[tommy234]

another thing i forgot to mention...if the engine is not running and just on accessory power there is no interference

 

[viwil]

Ground is still likely the cause