on my 95 4runner 3.0, I get a low hum/buzz sound out of my speakers... not sure what stereo mods were done over the life of the truck, but its quite annoying and curious if this has to do with the ground? Maybe not the actual truck "grounding", but maybe the radio ground?

Can someone tell me where my main body ground connection is? Its worth checking I guess..
thanks alot
Neal

 

does it have an aftermarket cd player and amps in the back, or stock? Does it get louder when you hit the gas?

 

^ Yeah good starting questions.

If its stock, check all the grounds.

If it is aftermarket, you may need to rewire. You may be getting electrical interference, also known as engine noise from the wiring set up. Separate the 12v wire from the RCAs and speaker cables, running them on separate sides of the truck. Then make sure that the AMP ground is good and solid. Check your RCAs for kinks and stuff like that.

 

Non-resistor spark plugs and / or ignition wiring could cause a buzz, as could a spark-plug wire that is damaged and is arcing to something, however the buzz would change in frequency with the engine rpms.

If the stereo / amplifier is balanced/transformerless, aka BTL (most modern stereos are and you can tell: if the stereo / amp has a [-] wire for each speaker it's BTL and if it has a common [-] wire for front/rear or left/righ or even all speakers, it's not), if one of the speaker wires grounds out that could cause a buzzing as can having the amplifier gain turned up too high or having speaker wiring or amplifier cabling running near the ECU (on the right side of the passenger cabin).

 

thanks guys.. yeah, its an aftermarket head unit that looks like it used to have an amp and speakers... Found some wiring here and there, but all equipment was taken out.. I assumed it was something with the stereo.. It does change freq when I change RPM..