For once I am not sure which forum to post this in, lol!

Anwyays, how do I troubleshoot the mysterious battery drain problem. Something is causing it to die.

Can someone please walk me through the troubleshooting procedure.

I need to insure that the battery is being charged (alternator working)
I need to insure that there is nothing draining it when the car is off (besides clock memory, ect)

Thanks!

 

The easiest way would be to jump start it, then take it to Kragen and ask them to do a load test on the alt. and battery. They have a computer/tester that will tell you what is wrong on the spot.

 

Probably Maintenance & Warranty forum.
Voltmeter placed across battery terminals while engine is running should indicate approximately 14 volts. At idle, may be slightly lower but revving engine to 1000 rpm should bring alternator output to 14v. Anything less will not charge battery and it will become discharged as engine is running. Anything exceeding 16 volts will overcharge battery and cause eventual failure, too.

The above test will only check voltage output, not current output, but in most cases is sufficient. Is drive belt for alternator adjusted properly for tension?

A tech might have a different method to check for shorts and other sources of current drains but you might try this:

Use 12 volt test lamp to check for current drain of electrical components. You can use a handheld ammeter for small current drains, too (not for something like the starter circuit when you crank it over). Unplug various connectors one at a time and insert test lamp or ammeter between power source (fuse box, battery, etc.) and component (radio, alarm system, lighting system, etc.) when component is turned off. Look for test lamp to light up or ammeter to indicate current flow.

How old is the battery? Is it a sealed, maintenance-free unit, or does it have removable vent caps to allow distilled water to be added? The factory Subaru batteries of some models like mine were not maintenance-free and required periodic topping off of electrolyte mixture with distilled water.

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0==WW==0
"…axles of evil…" - george w. bush

 

To troubleshoot short circuits in wiring such as possible ground to chassis, use test lamp.

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0==WW==0
"…axles of evil…" - george w. bush

 

HOLD ON HERE! IS THIS FOREALS?? mr imprezer needs help with his car??? LOL, just kidding alex! dude, just take a voltmeter to your alternator when the car's on to see if you're reading voltage. test the battery for charge. if you need a different battery that works but it's a regular size one, let me know. i have an extra one that you can use.

 

First off, do you have any extra electronics items in the car? i.e., amplifiers, woofers - something that would drain the battery?

 

No stereo, but the whole car has been taken apart more than once.

 

If it starts w/ a jump, I've found it to be the battery needs replacing. Does any of your acessories work? ie interior lights, dash lights, etc.

 

If it starts with a jump, it could be a bad starter.

 

If its a subaru factory battery and its more than a year or two old, its probably the battery.

because the factory batteries are pieces of crap

 

1 or 2 years and the batteries go dead........ouch!

 

If the starter was bad, the engine won't turn over whether it's a fully-charged battery in the vehicle or a jump start.

Alex is asking what is causing a drain on his battery, not about a starting problem.

--
0==WW==0
"…axles of evil…" - george w. bush

 

Same exact thing that happened to me, except I have a 1000watts stereo system + alarm thats really sensitive. for a about a month i had to either jump start my car or have someone to push. If leave my car sitting in the parking lot for more the 12hrs my battery would die, when I'm parked and listening to the radio (volume is minimal) my of turned off it battery would die after 5mins. For awhile I thought that it would be something else like maybe my alternator is not charging my battery properly or there something that discharging my battery. So I got sick of it and finally bought an optima yellow, and ever since then my battery hasn't died or needed to be jumped.

 

Best way to check for parasitic drain with the engine off is to disconnect one of the battery terminals and connect a milliameter in series between the battery post and cable terminal. Make sure the car is in full "standby" mode- key out, all doors and trunk closed, interior light off. You should see well under 100ma drain, probably closer to 10ma if all is well. If it's much above that, in the hundreds of ma or more, there is an excessive drain someplace. Find it by disconnecting suspected circuits/devices one at a time until the drain drops back down to normal.
While the meter is connected, do not turn the key on or attempt to start the car, this may destroy the meter (or at least pop its internal fuse). In fact don't put the key in at all until you complete the test and reconnect the battery terminal.
To verify the battery is charging, measuring the voltage across the battery is usually sufficient. However you also want to be sure the battery is in good condition, so it should meet the following conditions- at least 12.5 V on the battery with the engine off and after sitting for a while, water levels in cells full and equal (if applicable), hydrometer test of cells shows all w/good and equal charge levels (again if applicable). If the battery is sealed it should be tested with a load or conductance tester (conductance test is preferred as it is non-destructive).
With the known good battery, there should be 13.5-14.5 V across it with the engine running. For a more thorough charging system test, a shop can put a scope on it to check for alternator function. Some problems such as bad diodes can only be ID'd with a scope.

 

Yeah, Mulder pretty much answered my question here. Now I just gotta do all that and see what is going on...

Also, what battery should I get? I figured I should get a new battery anyways.