1999 Chevy Lumina Battery, Alternator, Fuses?

1999 CHEVROLET LUMINA
130,000 MILES • 6 CYL • 2WD • AUTOMATIC
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MICHELOB32000
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My car is draining its battery while my car is off. I have noticed that my radiator fans seem to run speratically when my car is off. Usually when I notice this, my interior lights are off and my radio is completely reset. But my car would start up just fine. What is weird is that my car has a sticker that says the radiator fans will run when my car is off, so I'm guessing that it may not be part of the cause. Do you have any estimates?
Sep 29, 2008 at 4:33 PM
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RENAUDTN
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The fans coming on after you turn off the car is not necessarily abnormal; the engine gets a little hotter even after you turn off the car, and the fans help to cool it down.
Now your battery:
I guess I'm a little confused because you say your battery is draining but your car starts up fine... if your battery was really draining, you should have trouble starting the car (slow cranking), or your car may not crank at all.
If you have a voltmeter, check voltage at the battery with car off (should be 12.6V), and check with car on (should be between 13.5 and 14.5 V). If you have less than that with car on, there's a problem with your charging system (possibly alternator).
You can also take your battery to an autopart store and get it tested to make sure it can still hold a charge.
A battery's life is usually around 4 or 5 years, so if your is older than that, chances are you need a new one.

Okay, now let's say your battery is good, your charging system is good, but your battery keeps draining: something is pulling too much amps after you turn off the car.
Usually, a parasitic drain should be less than 50 milliamps one hour after you turn the car off. If you have more parasitic drain, pull one fuse/relay at a time until the reading on your voltmeter drops. Once it drops you know which circuit is draining too much current and you'll have to Check the relay, switch, modules on that circuit and replace the defective component.
Sep 30, 2008 at 11:18 AM