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Dead battery again

I’ve got a 2001 Chevy Impala that needs jump started every 2-3 days. It has a new battery (1 month old), the electrical system has been checked over twice by our local Chevy dealer with no problems found. All they can say is something is draining the battery. Any ideas out there?

Another dealer doesn’t know how to do their job? The tech/mech isn’t trying hard enough but still takes your money.

What have they checked and what were the results?

These current drains are sometimes hard to find. They don’t pull enough current to blow a fuse. Check to see if the light in the trunk, glove compartment, underhood light, or center console is staying on when it shouldn’t. You might even remove the bulbs temporarily to see if the problem goes away.

Look for an electrical specialty shop. These places are often better equipped than a dealer to solve these problems.

I don’t want to say electrical work is such a difficult area but the tech must be specifically trained and his pride must be motivated. It is a matter of pride to not accept that you can’t find the draw.

It should be straight-forward to find a constant current draw–you put an ammeter between the battery and lead and see current flowing.

If this is intermittent it might be harder to spot.

Do you have a remote start or after market alarm? These vehicles have a body computer (BCA?) that can sometimes be “fooled” by cheap and poorly designed after market alarms / remote starters.

The result is that the BCA remains active all the time, when it normally would power down after ~20 minutes of inactivity.

The result is that every 2-3 days of disuse (or short use) you wind up with a dead battery.

Someone w/ experience w/ this issue will hopefully be able to add more–

If you’ve checked everything by pulling fuses one at a time and found none of them make a difference, try disconnecting the main connection (heavy wire) between the battery and the alternator. One of the main alternator diodes may be leaking current.

They said they checked the electrical system and it was fine, alternator was charging and the battery was fine.

I do not have a remote start on it.

That’s probably my next move, I really don’t want to start replacing the alternator, starter,battery cables or whatever if I’m not sure it’s going to make a difference.

OK, Shade tree mechanic figure out how to find the drain. Disconnect positive cable from battery. Touch to post and see spark. Remove one fuse and try, if there is still a little spark replace fuse keep repeating through the fuse block until you isolate a circuit, once the circuit is isolated start narrowing down the components, Caution each battery disconnect may reset the computer so you may want the additional power brain saver that plugs into the cigarette lighter.

Best way to check for a drain is with an ammeter. However, it takes a while for all the computers in the car to go into ‘sleep’ mode, so you have to either be really careful as you pull off the cable with the ammeter attached already, or you have to connect the ammeter and go away for a while and wait for all the computers to shut down before reading the ammeter. Normal drain varies, but anything over 50 mA is too much.

I discovered that the reason that my daughter’s car would drain the battery after several weeks of being parked was that the aftermarket CD changer in the trunk was hot all the time and was drawing 50 mA all by itself. With the CD unplugged, the drain dropped to 10 mA.

You just can’t tell people to purposely cause a spark at their battery. Every step known to man show be implemented in a effort to never cause a spark around a battery. I have never caused a explosion of the gases that are present around the top of a battery and I never knew anyone who did themselves but the theory of how a explosion could occur is sound, besides you need to know the value of the amp draw and just looking at how intense the spark is will not get you that information.

No sparks around batterys, this rule is just as important as not getting under a car that is not correctly supported.