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Car battery dying please help!

I have a 2007 saturn vue whos battery wont stop dying over night. i replaced the battery it wasnt the issue and ive had the alternator and battery checked by different sources to make sure they were both running well. so its dying and its not from battery or alternator. when i jump it everything works fine only thing is i notice that when i jump it and it turns over as soon as it starts turning over the horn goes off once… also in the past the car alarm has gone off randomly at night. this is a re-occurring problem over the past 6 months. it went away for about 3 months and now its back. other things, when it dies sometimes it fully drains the battery other times everything will turn on in the inside but it wont have enough juice to turn over. im not great with cars so i dont really know what to do now, hopefully someone has some sound advice. thank you

Clearly, somebody needs to perform a parasitic draw test, and also check out that car alarm

Is it by chance an aftermarket alarm . . . if yes, I suggest you disable and/or remove it completely, because in my experience they tend to be overly sensitive, to the point that a slight gust of wind will trip you alarm


I think DB above is correct, there’s some circuit that is staying on and draining the battery even with the key off. And the car alarm would be the first suspect. You might be able to turn off all electricity to the car alarm by pulling a fuse, depending on how it is wired up. If so, and you’re willing to take the risk of no alarm, try that. Next would be the parasitic battery drain test. Very easy for a shop to do that. It tells you whether or not some circuit is staying on when it shouldn’t. Then you’d know for sure.

Another idea, the battery and alternator can be working perfectly fine, but if the battery isn’t robustly connected to its cables, this symptom can result. You could ask a shop to remove the cables and clean the posts and connectors for you. At the same time they should clean the top of the battery, as surface contaminates can conduct electricity between the posts and cause the battery to discharge overnight. Have them check the battery fluid level too.

One other thing, when you think the battery is dead, what exactly is the symptom? You turn the key to START, and it clicks? Or makes no noise at all? Or cranks – that rrr rr rrr sound – but won’t pop and run?

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i went ahead and bought a multimeter it looks like a parasitic draw but the odd thing is the draw is coming ever 10 or seconds. so its fine then it jumps up then back down and repeats im gonna try pulling fuses first if that doesnt fix this then ill go ahead and pull out the alarm system. Because i really do think it has something do with that considering while trying to undo my battery terminal the horn started honking for no apparent reason so i went to the fuze box and when i tried to take the horn fuze out it honked at me so i just popped it out.

When the horn comes on for no reason it makes me think either the battery voltage is low enough the electronics aren’t stable, or the car alarm is going off for no reason. Is there any indication a door switch isn’t working correctly? Like the dome light flickers? Or it doesn’t turn on when the door is opened like it should?

i took my dome light fuse out because it kept coming on randomly at night this was back when i alarm was also randomly going off at night. if you think that its one of the doors then how do i check for that? can i use my multimeter to check for it being a door sensor?

That was my first thought too. Especially when reading that both the horn and the dome light are coming on for no reason.

If this is an aftermarket alarm system, see if it has a separate fuse. It might even be a line fuse. If it does, try removing it and see what happens. Note that it MAY disable the car, but I’m hoping it’ll just disable the alarm.

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Several years ago, my brother bought a 10 year old Toyota, which was in fine mechanical shape, and for a decent price. But it had a cheapo aftermarket alarm system. Not only was it so sensitive, that EVERY car driving by would activate the alarm, but it also caused starting problems. In the end, the real fix was to remove it completely, because it was teed into seemingly everything. Took a little while, but that was the end of the problems

Start by replacing the dome light fuse so the dome light works, then testing door by door, manually pressing the little button that turns on the dome light when the door opens, until you find which one is intermittent. It will probably be the driver’s door, b/c that’s the switch that is used the most. Then remove it and test it w/your multimeter. You may be able to clean it out with some electrical contact cleaner. Otherwise replace it w/a new switch. The alarm monitors that switch to see if the door is being opened. If the switch fails the alarm thinks someone is trying to break into the car.

I usually recommend this , has helped a few posters and friends.

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