grounding issue?

[dudeguy]

hey again guys
my stereo in my 94 buzzes constantly it drives me nuts.its all the speakers and goes away when i turn the stereo off so im sure its a ground issue,also it is at its loudest with the lights off and gets quieter when i turn the lights on and the noise goes with the rpms as well.
also about a month ago my fuse for power mirrors went and i replaced it and the pigtail CAUGHT FIRE!!!!
so,where should i look for grounding issues?the stereo is grounded to to chassis so it isnt that.could it be the headlights?or should i rip the door apart and check the mirrors?
thanks

 

[Rick]

Check at the battery. Sometimes the cables can get badly corroded under the insulation.

 

[awood]

Check out this link I recently found - specifically the "voltage drop tests" and the "quick ground tests" sections. I think you'll find the whole article interesting.

http://www.fluke.com/fluke/usen/com...cleCategories/Electrical/DiagnoseVoltDrop.htm

 

[dudeguy]

thanks guys.it wasnt the battery.ive narrowed it down to the headlights,any ideas on where those might be grounded?I cant seem to find anything on it

 

[tweakedlogic]

Headlights are constant load with no moving parts. very doubtful they are causing the noise.

Try changing the location of the head unit ground. Make sure other accessories are not sharing power or ground locations with the head unit.

Is there an external amplifier? If so, and the head unit ground doesn't fix it, check the amp ground.

Make sure you have good connection from the alternator to battery, battery to chassis, engine to chassis, battery to fuse block. If you have an external amp it's a good idea to go ahead and change all of these to heavier gauge.

 

[dudeguy]

no amp.head unit is grounded by itself seems good.where do i find all of those grounds?