What is draining my battery?
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From: Schaumburg, IL
What is draining my battery? Car has been sitting in the garage the last two weeks and I go out to start it and its completely dead, the keyless entry doesnt even work. The battery is only two months old, so it seems there is a constant drain on the battery coming from somewhere. Any ideas?
Teching In
Joined: Jul 2005
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I have a similar battery problem that only occurs when it's cold. between 30 and 40 degrees it turns over slowly, but starts and the alt. shows a strong charge going into the battery. below 30 degrees I have to jump it off. Same thing happened last year and I replaced the battery, now the same thing again. It seems to me like something is draining the battery. I make alot of short(10 mile) trips and maybe the battery dosn't get fully charged again.
I found that sometimes the light in the glove compartment is on with the door closed. If i adjust it a little it turns off. Could be that or any other light in the car. Check under the hood, center console, rear hatch lights, door handles, that kind of stuff. Oh, also check your interior dimmer switch (usually the most obvious problem you'll find) and make sure you don't have the interior lights switched on. If you can't find a light problem, you might want to check some relays. The old fashioned way (and more difficult way) is to disconnect the battery terminals if you're not going to drive it for a while.
Staging Lane
Joined: Mar 2005
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From: Brighton, Michigan
Pull out each fuse, and measure across each fuse clip terminal with an ammeter to see which circuits are pulling current. A few will have some draw, like the radio and BCM, but if you see any particular circuit that looks like it is drawing too much that might be the problem...
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Originally Posted by 01formula6
Ok that's a good idea, I'll have to borrow one from a friend. Will the battery being dead effect this test, or do I need to charge it first?
Originally Posted by jimbonzzz
Pull out each fuse, and measure across each fuse clip terminal with an ammeter to see which circuits are pulling current. A few will have some draw, like the radio and BCM, but if you see any particular circuit that looks like it is drawing too much that might be the problem...
I had the same thing happen and it ended up being my battery cables weren't screwed on tight. Make sure you tighten them real good. Replace the battery as it probably won't hold a charge from being drained so much. Connect the cables and see if that solves the problem.
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From: Schaumburg, IL
Originally Posted by joshp14
Another way to do this is to remove the negative battery cable, and put your ammeter in series between the cable and the battery. Watch your milliamps with all your fuses in and let it stabilize, then begin pulling fuses out one by one and watch your ammeter, if it drops when you pull that fuse, you know that you have drain in that circuit. Normal drain should be 30-40 mA.
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Ok, here is the update. I got the battery charged and then tested at Autozone, and it checked out fine. Went back to the house and hooked up the ammeter to see if there is an unusually high drain on the battery. Result was 300 mA. This seems pretty normal. I didn't think it was a charging issue because my voltage never drops when I'm driving around and the only time there is a starting issue is when the car has been sititng 2+ days. Anyone have any thoughts on this?
My car has these sympotm as well........now starting if untouched for 2-3 days.....
00 TA...new battery, alt, starter.........tons of add on gizmos for the N02 and gagues.......
Ive been trying to find the problem for sometime now.
i hate everyone knowing how sweet my ride is and then the mother F*cker doesnt start on me......
00 TA...new battery, alt, starter.........tons of add on gizmos for the N02 and gagues.......
Ive been trying to find the problem for sometime now.
i hate everyone knowing how sweet my ride is and then the mother F*cker doesnt start on me......
Thread Starter
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From: Schaumburg, IL
The 300 mA was not a typo. That seemed like a pretty reasonable amount to me, you guys are positive it should only be about 30 mA? Would an extra 270 mA really cause the battery to go dead in 2 days?
Well when I had my radar detector plugged in (before I hard wired it) and left it on, it would drain the battery in 2 days, especially when it got cold. I dunno how much that would draw but it can't be much, so I'd say yes
BTW now that it's wired to go off and on with the car I haven't had a problem starting it even after a week of it just sitting (and that's in 20* weather)
BTW now that it's wired to go off and on with the car I haven't had a problem starting it even after a week of it just sitting (and that's in 20* weather)
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Ok, I finally figured out that the problem is somewhere in the power accy. circuit. This includes the parking lamp relay, hatch release relay, power mirror switch, radio, shock sensor, and instrument cluster. Before I go trying to figure out exactly which one of these is the problem, has anyone experienced any issues with these? Which would be most likely to be the problem?