qwuc

So, recently my car has not been able to turn on by itself. I installed a AMP and did it wrong. I ran the AMP and didn't have a remote wire so it just killed the battery. No big deal. Unplugged amp from battery, and charged battery. Seemed good for a week. Now it won't hold a charge, only turns on and will run fine when I jump it. My only concern is, I idle it, and it puts out 16 volts, and about 12.5 when off. I went to Autozone, had them try it, battery was pushing 11.2 with car off. ALSO, replaced my alternator, and still no fix.

So my thinking is, my battery is dead since it can't hold a charge. Also I believe the multimeter I'm using is bad also since it was reading 1.5 to high. Any thought? No fuses blown either.

drhawkinz

The amp wire on the radio tells the amp when to turn on. If it isn't connected then amp should never turn on. I would chase your power and ground wires and make sure you don't have nick in them. Maybe they are grounding out when you ran it through the firewall or something.

Plus even if somehow the amp was on AND it wasn't playing any music then it's just powering the LED lights on the amp so I wouldn't think that would be enough to drain the battery.

jordan1794

You replaced alternator before the battery?
Usually it's the other way around...but hey, you won't need another alternator for a good while.

If the alternator is charging at 16 volts that means it is desperately trying to restore voltage to the battery, which would be indicative of a battery that won't accept a charge.

You already went the most expensive route...normally I'd tell someone to replace the battery, as compared to a new alternator is relatively cheap...

Maybe find a friend with a known good battery, and borrow it for a day(or week?) and see if it works right?

jordan1794

When you run a battery dead you do irreparable damage...the older the battery, and the more time it has been run makes the damage worse and worse.

jordan1794

11.2 with the car off is kinda low, but still functional...however the number you need is how many cranking amps it has.

qwuc

Yea I've checked all that, I ended up just removing the whole amp.

qwuc

So the battery is most likely dead, I appreciate it a ton, I can go grab a new one sometime soon. Thanks again man, I'll report back on how that works.