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Buick dead battery

Have a 2003 Buick Century. Wife took it to the airport, left it there for a few days and when she came back, the battery, which had shown no previous signs of trouble, was dead. With the help of a kind stranger, she got it jump-started and drove the 30 miles home. When I tried to restart the following day, battery was dead again.

I am mechanically-challenged. Is it the battery or the alternator that’s shot?

Thanks.

Can’t tell until some testing is done. If this is the original battery, suspect that battery is probably the problem. It may be at the end of its useful life.

I would charge it overnight and then drive to a place like Advance Auto, where they can test the battery and alternator for free, in most states. Call ahead to make sure you aren’t wasting the trip.

Given the age of the battery, you could also buy a battery (Costco appears to have best prices and best warranty these days), install it, and then go get the alternator checked to make sure you don’t also have an alternator problem. If you don’t want to do that, using a place that installs batteries (Advance Auto, Walmart, Sears, etc) would be your better option. Walmart may not do on-car alternator testing, though.

Some of this testing can be done at home if you have a volt meter and can measure the charge coming to the battery. It will tell you whether the alternator output is OK or not.

Thanks for the reply. No place nearby to do the sort of testing you recommend. But I do have a battery charger. I have the battery on a slow charge. When I started the car (with the aid of the charger) it showed that the battery was receiving 14.6-14.8 volts. Also, the alternator idiot light (if the car has one) isn’t lit.

Thanks again, DocG

Doc, The Fact That It Won’t Start, But Will Start With A Jump, Will Continue To Run For 30 Miles Afterwards, Points To The Battery Being Bad. It Isn’t Certain, But Very Likely.

How Old Is That Battery ?

Also, is it possible that your wife left something on, like some lights ? That would run the battery completely flat and if it was old and weak could have killed it (no big loss). The 30 mile drive would ordinarily recharge a depleted battery that still had some useful life in it, providing the car’s charging system is functioning.

How old is that battery ?

CSA

Can’t find a sticker or anything else on the battery that indicates its age. We are not the original owners and there’s no way for us to find out if the person we got it from ever changed the battery. Nothing had been left on in the car.

Doc, Is The Battery A Delco Brand Battery ? If So Then Chances Are It Is The Original Battery.
How Long Have You Owned The car ?

CSA

It is most likely a failing battery and if no testing is available replacing it seems your best option.

A Used Car With A Battery Of Unknown Age And History That Went Dead . . . I Agree With Rod. Replace It. That Way You’ll Know Its Age And History, Regardless.
CSA

The battery is an AC Delco 6-year battery. We’ve had the car three years. The original owner was the prototypical white-haired lady. Everything under the hood is clean and new-looking, including the battery so I’m gonna hazard a guess that this may be the original battery and replace it.

Thank all of you for the help. It comes in really handy right now.

I’d say battery. 30 miles is not much to charge a fully discharged battery. It should have been put on a charger at least overnight. I had the same experience. Car left at the airport but wife’s flying partner did not get the trunk closed all the way so the light was on. It was a fairly new Delco battery and came back to life with a good charge. They don’t like being discharged so depending on age, replace it. You may also have a drain someplace.

To test the alternator, start the car, disconnect any battery charger, and turn on your headlights, heater fan, etc. You should have around 13.5-14.5 volts at the battery. Any less than 13 and I’d say your alternator is weak. A fully charged car battery with no load on it (engine off, battery cable disconnected) should have around 12.4-12.6 volts I think. If you have less 12, the battery is either weak or not fully charged.

You’re Welcome. Three Years Of Use From A Used Car Battery Is Pretty Good.
On Used Cars If I Can’t Determine Battery Age Then I Just Replace Them. They’re Easier To Deal With On My Schedule (Think: Summer, At Home), Not The Battery’s Schedule (Think: Winter, Miles From Anywhere).

CSA

I had my battery go flat every week in my volvo. The battery was fairly new, it got charged up and then went flat again - drove me nuts. It turned out that after some very hot days (48C) here in Oz, the glovebox door/hatch had warped, so that when the hatch shut, the internal light (inside the glovebox) was still on. Once I realised (by listening to the ‘click’ of the switch), I added some padding to inside the hatch to ensure that when the glovebox door shut, the light went out - ta da!! no more flat batteries!!. And yes, the mechanic can measure these things too, by the way…:wink: