Twice in the last 6 weeks has my battery completely drained on my 2020 Mazda 3… engine is off, lights are off, no obvious culprit… has anybody else experienced this? any idea what might be causing this?
You have a faulty new battery or a parasitic drain. Trunk or glove box light not shutting off or other accessory nit shutting off. A shop can attempt to find it if not intermittent or you can google to see a whole host of diy advice.
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Type “parasitic drain testing” in Google or on YouTube. Something in your car is not “going to sleep” when you turn it off. Or your new battery is faulty… have it tested, too.
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Did you replace your old battery for the same reason??
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It seems like it’s an occasional problem. It occurs every three weeks or so. What is similar about the times it happens? Did you leave something plugged into a USB port for instance? If you can make it happen you will know what it is.
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There is a service campaign for 2019-2021 Mazda3 to address a problem with the Climate Control Unit and the Body Control Module causing a battery discharge.
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Hi all! Thanks for all the tips! I changed the battery again, and again it drained after sitting in the driveway over 4-5 days. I’ll investigate following your advice and will report back. Thanks!
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Before you ruin another battery why not call around and find a shop that can see if you do have something draining your battery that can be fixed .
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Some aftermarket devises may cause a battery drain. examples in link..
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It could be a parasitic drain from something like the infotainment or smart key system. A mechanic can test for it.
Parasitic drains. With older (simpler) cars a good mechanic would hook an ammeter between the negative cable and the neg battery terminal. It should show the drain. Then he goes through each fuse until the meter drops to zero. There’s your component that’s causing the problem.
With newer cars who knows…
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The OP was asked questions that needed answer for us to help out, as well as given great advise to do/check and the only reply the OP made was that they threw another battery at it and it did the same thing… It seems that the OP is not really interested in help at this point…
OP, some say the definition of insanity is to keep doing the same thing hoping for a different result… You have now installed 4 NEW battery’s with the same thing still happening…
Here, Mustangman posted this a while back, it applies to you also.. Unless you are buying battery’s in a dark alley from a shady character out of the back of his van… lol
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I have a friend with a 1995 Lincoln Town Car. Low miles, he’s retired and doesn’t drive a lot. A few years ago his battery was going dead if he didn’t drive it after a few days. His redneck fix: A battery disconnect switch. Very common in boats. So he pulls in his driveway and turns off the disconnect. This car is old enough it doesn’t have little computers that have to be powered all the time.
Powertrain control modules and transmission control modules had adaptive memory in the 1990’s, people just didn’t worry about those things back then.