If a car’s battery is fully drained due to disuse for a couple months, then it’s jump started and everything is fine, has any last damage been done to the battery? I ask this because the battery now is dead after only 4 weeks of non use, and in the past that’s never been a problem.
Did you make sure it was fully charged after the jump start?
Modern cars use a lot of juice, so just driving the car around for a bit won’t necessarily charge the battery fully - my mechanic told me to buy a battery charger and preferably fully charge the battery once a month, when it happened to me.
They’re pretty cheap here (so I imagine they’re almost free in the US) and nifty to have around.
How old is the battery? More than three years?
I haven’t checked battery date, but the vehicle itself has about 50K miles on it and is about 2 years old (former rental vehicle so take that for what it’s worth – it’s been super solid otherwise). I’ll check the battery date when I go out to jump it.
It’s a 2009 Mazda 5 Compact Wagon.
My issue if that this is going to be a recurring thing I should probably just go ahead and swap out the battery now – I figure most auto parts place can do a battery swap for me (I don’t have many tools handy at this residence).
The other thing to be wary of with swapping a battery is that when removing it, you can lose all of your security data for things like radio. That can be a pain in the arse tracking down the pin (if such a thing is in the car of yours, I don’t know). Certainly a good plan to get a place to do a battery swap. What they have is a little tool that goes into the cigarette lighter/power socket thingo which keeps power running through the car computer and holds the various security settings.
After three years or so, a car battery can start to fail. Not a solid rule of course, many can go even longer (more than five years in some cases). And by having a charger attached to a battery when the car won’t be used for a long while, that can really prolong their life.
It just so happened to be that my battery failed the other night. I knew it was on its way out, though wanted to eliminate the cold (Winter/early Spring here in Australia) before going down the replacement line. Of course, it finally died when at a shopping centre (which wasn’t too bad). I simply believe if it seems to be on its way out, it is probably best to replace rather than being stranded somewhere potentially undesirable.
It holds less charge every time it is fully drained. Something to do with SCIENCE. You should turn your unused car on for a few minutes every week or so and possibly drive it around a little.
I imagine that if your battery’s spontaneously dying, you’re not terribly worried about your radio settings. But that’s just me.
Get a trickle charger – one that’s safe to leave on that battery the entire time that the car is sitting (instead of a charger that should be disconnected after the battery is recharged). Plug 'er in, and get all the way charged. Use it for a while, and see if it seems to be an issue.
If you’re going to park the car again for more than a week or so, throw the charger back on the battery again so it doesn’t drain out.
Also – you can go to most auto parts stores and they’ll run an electrical check for free. They can tell you if your battery is still capable of holding a charge.
It’s possible.
I ask this because the battery now is dead after only 4 weeks of non use, and in the past that’s never been a problem.
Go to an auto parts store that sells batteries and ask them to test your battery.
In the future, you should buy a trickle charger and keep that hooked up to the vehicle while it’s not being used. That will protect your battery from harm when the vehicle is not being driven.
I just had my battery replaced last week. Unless the mechanic was lying to me – very easy, for I know little about autos – batteries can take & hold a charge, but still be slowly dying. If I remember correctly, the sequence of steps was:
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My dead car got a temporary charge from tow truck driver, who suggested I follow him back to the repair shop where the battery could be checked.
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Battery & charger are checked and seem to be fine. Mechanic suggests I either drive the car around for a little while to build up more of a charge, or he’ll hook it up to a battery charger for 20 minutes while I get a cup of coffee. I used my AAA car for the tow truck, so he said no fee would be assessed for either the battery check or offer for a charge.
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I decide to get the cup of coffee & wait 20 minutes. He checks the battery again after charging and says, “Huh, that’s weird.” Apparently the battery was only charging to about 2/3rds of what it was supposed to – something like 4800 volts/amps (physics memories far too faded) instead of the proper 6500. He said I’d be able to drive the car & the battery will hold the charge, but the overall battery health is compromised, it’s slowly dying, & it’s just a matter of time before it fails.
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Replaced the battery; everything is right again with the world.
So while I think the suggestion to have the battery tested at a auto parts store is a good one, I’d see if they can assess the total capacity as well. If I had stopped at the initial check at step 2 above, the battery would have seemed fine when it actually wasn’t.
It’ll take at least 15 minutes or so to properly test a battery, because it takes about that long to get rid of the surface charge in the car battery formed while driving to the auto parts store that will otherwise skew the test.
I can’t do a trickle charger (condo parking garage) or start it occasionally since I’m only at the residence part time (once a month). For the past year once a month was never an issue with keeping it charged, but when I skipped a month it died and then this month (only 30 days elapsed) it’s dead again.
I’ll hit a battery store on Tuesday. Thankfully when I do drive it, it gets driven a lot so it should stay charged on its own until then. Thanks for the help!
Are you disconnecting the battery when you know the car won’t be used for awhile? That’s usually recommended rather then just letting the car sit.
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A lot of our race cars have battery disconnect switches as they are usually super light batteries with just enough juice to crank the engine 5 or 6 times, so they go dead within a week of disuse. Disconnecting the battery is fine, but it comes with a downside which is that the ECU forgets all of its real-time tuning and has to relearn it… usually takes about a tank of gas.
On a daily driver, it also means your radio will probably forget all its presets. Which is why the battery tender would be a preferred method. But, hey, if the cars gonna be dead when you get back to it, you may as well just disconnect the battery so that you at least don’t damage it by the discharge.
Link to one a buddy of mine uses on his Caterham 7:
http://www.google.com/products/catalog?q=battery+disconnect+switch&oe=utf-8&client=firefox-a&cid=16092400149396143736&ei=9Zk_TLzyNZ2oigTP24XSCA&sa=title&ved=0CAcQ8wIwADgA#p
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A lot of our race cars have battery disconnect switches as they are usually super small batteries with just enough juice to crank the engine 5 or 6 times, so they go dead within a week of disuse. Disconnecting the battery is fine, but it comes with a downside which is that the ECU forgets some of its learned parameters and has to relearn them… usually takes about a tank of gas, and not something that would be a main concern on a daily driver.
On a daily driver, the downside is that your radio will probably forget all its presets. Which is why the battery tender would be a preferred method. But, hey, if the cars gonna be dead when you get back to it, you may as well just disconnect the battery so that you at least don’t damage it by the discharge.
Link to one a buddy of mine uses on his Caterham 7:
http://www.google.com/products/catalog?q=battery+disconnect+switch&oe=utf-8&client=firefox-a&cid=16092400149396143736&ei=9Zk_TLzyNZ2oigTP24XSCA&sa=title&ved=0CAcQ8wIwADgA#p
No, mostly because I figured that the downside (as mentioned earlier via ECU/radio stuff/etc.) was greater than the upside.
Honestly, I guess being a car n00b, I didn’t realize that not running your car every month was really that bad.
On a related topic, I got one of those little car starter battery thingies, and it’s like goddamn magic. $25 from Amazon I think, and everyone should have one.
It isn’t just the battery, but all the moving parts and various seals that exist within the car’s engine and accesory systems (like air con) will benefit when it is started and run little more regularly.
Or at least, that is a lesson a mechanic told me.
I don’t know what else you can do if you know you will be leaving a car for a long period of time, but I do know that unplugging the battery is normally considered part of that process. How much that has to do with your situation I don’t know, but getting the battery tested seems like a no-brainer at the very least. I had a battery go bad earlier this year, and it was way beyond the 3 years or so they recommend you start paying close attention to them. But I figured I’d see some signs before it finally died. Turns out I was wrong about that - it just up and died out of nowhere.