Car battery seems to keep dying and I don't know why

[BigToque]

I've got a 2002 Saturn SC2 and there seems to be a pretty big problem with my battery - it keeps dying.

I've got an alarm system and a pretty big stereo system that I thought my be improperly installed, but two separate locations test and say that there is no power being drawn other than from the alarm when the car is off (and that what was coming from the alarm wouldn't drain the battery).

I'm not sure what to think but if I leave my car sitting for more than 3-4 days, it just won't start.

Last night I used my car. Tonight I tried to start it and it's just dead.

This is a new battery as well. I think the old battery had the same problem, but I know I also completely ran it down a few times by leaving the lights on, so I just figured it needed to be replaced, but it's happening again.

If my car isn't using any power when it's just sitting, how could the battery die?

 

[LTC8K6]

Your best bet is to first get it to a place like Auto Zone that will test the battery and the charging system for free.

That test result would determine your next move.

If you have already determined that the alternator is charging the battery properly, then you might need to look into the connections, the solenoid, etc.

Keep in mind, that the drain may be intermittent, like a sticking brake light switch.

One test you can do is to charge the battery yourself overnight with a good battery charger, and see if the car will start after sitting for 3-4days.

 

[zoiks]

Simple test. Disconnect your stereo system completely and wait a couple of days to see if that was the problem. Do the same with the car alarm next if the problem persists. I remember my previous car had the same problem and it was the shoddy car stereo installation.
Also it could be the alternator. Check the voltage on it when the car is running. I believe it should be around or over 14volts.

 

[soydios]

battery could be dead. alternator could be dead. your measuring tool could be dead.

eliminate all 3 possible errors by going to Autozone or somewhere and getting the whole thing tested.