CRAZY electrical current/noise issue!

**sq_geek** · 09-26-2004, 09:07 PM

Listen to this..

I was having some system noise aka background noise in my system (car computer + amp + speakers) and so I have been trying to isolate the issue for some time now (several weeks).

The noise is there when the car is off -- heck, even when the car computer is off but getting power fed to it.

So I finally heard about "ignition buzz" so I decide to try bypassing the ignition and just hard-wiring the stereo.

So I do and voila - no noise! BUT, as soon as I turn on my ignition (note: not the engine, just acc.) it is back.

Then I shut off my car. Then it is still there (cuz computer + amp is still hard-wired). So this is weird now because the circuitry which is causing the noise is STILL closed and the noise persists yet it was not there before I turned on the car.

Then I open my driver's side door and close it. Voila - noise gone.

So something weird is happening.

I haven't gone messing with any factory wiring -- don't worry, just basic car audio wiring, like running a wire from the batt to a distro block to my amp + pc, and then a ground wire from the chassis to my ground distro block to my amp + pc.

Any idea what could possibly be causing this?? This is crazy!!

Thanks,
Kevin

**trdcpu** · 09-26-2004, 09:26 PM

connect a wire to every piece of metal in your car, then connect that wire to a large metal rod, then burry that rod deep into the ground. should fix the problem.

**sq_geek** · 09-27-2004, 06:18 PM

har har, very funny..

**techeros** · 09-27-2004, 06:31 PM

I have had similar problems. I noticed it when I plugged my power inverter into my new truck cig lighter and used my laptop for temp purposes...man talk about a buzz noise. When I disconnected the power inverter and ran from battery, sounded great. I think it has something to do with the power inverter and a grounding issue. I can't put my finger on it, but keep me posted on your efforts. I will be installing my new system soon. I am considering using a UPS in the setup...

**snmnetwork** · 09-27-2004, 06:33 PM

make sure the wire coming from the battery is on one side of the car, and the rca jacks and speaker wire is on the other. Ground the amp to the chassis of the car.

**blackpacu** · 09-27-2004, 06:34 PM

Do you have a inverter in your set up?
I know my system has a buzz form the inverter, depending which one i use it can get pretty bad too. I've seen people get rid of this with a ground loop isolator, not the best solution, but it does work

**antimatter** · 09-27-2004, 06:55 PM

Is it possible that you have a short somewhere? or that the noise is being picked up from the wires that controll your power windows/locks?

**lawrence** · 09-27-2004, 07:23 PM

does your dome lamp go off as soon as you shut your door or does "dime down" then go out? it may pulse ground to dim your dome lamp. dont know what kind of car you have, but many cars use this to dim the dome lamp through the body control unit.

**sq_geek** · 09-27-2004, 09:41 PM

No inverter
RCAs are 1m run direct from pc to amp - not near any other wires
Dome light does stay on, but I don't think this is the issue -- have not tapped into any wires except 1 for remote turn-on lead
Not using a head unit - just a pc