I have my car battery pluged into a car charger to fix my wiring with my dash lights now im confused i would charge my battery and i would unplug the battery charger and i would listen to music and stuff with the stereo before, i unpluged it recently and i turned my acc on my ignition and then i hooked the stereo up again and my voltage meter went up to 18 and it was static through my spekers anyone know why it would do this?

Get a new battery for your voltage meter. Mine decided to tell me I was running 16 volts without the car being on.. Replaced the battery an it read normal again. As for the static, make sure you didn't forget to put the antenna wire back inside the deck.

I have a guage for my voltage not a hand held meter but my hand held one does the same thing is it because i need a new battery for the car?

The battery can't provide 18v by itself, you sure you didn't leave the charger hooked up?

Yeah i forgot i did. but why is it shooting up to 18 volts? it didnt do it beore

What he is saying is are you sure you didn't test the battery voltage with the charger on? I can't see a 12v battery supplying 18 unless its bubbled and overly charged. Try another volt meter.

Yeah i know i had the charger plugged in i forgot to discconect it. But that still doesnt make any sense to why it would go to 18 volts because you get more then 12 volts if you read it on the meter if you put positive and negative together but then you ruin the battters. What im saying is that even with the charger if something wasnt broken then it should read 12-13 volts with the stereo connected. i mean like if you took a battery charger to your car right now and hooked it up to your battery and read the voltage with your battery and your stereo connected it shouldnt be 18 volts.

My guess is that the charger malfunctioned. It shouldn't ever put out 18v but dumb ones with high current settings might to try and force 20A into a battery that doesn't need 20A.

ok this is what happened today. I hooked the charger up, my voltage gauge read 12 volts. now when i ground the stero wire to hook the stereo up in shoots it up to 18 volts. its only when i connect the battery.