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Discussion Starter · #1 ·
My battery is still dying if I don't run my car for 3 or more days. The battery was bought this passed august. My battery has never dischared this quickly even when I had the old battery while teh two was being stored with the alarm armed. What could be drawing the power this quickly when the only thing that is running while the car is off is the alarm? Should I buy a new alarm or alarm battery, or is there some other issue?
 

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You might have a short in the system somewhere, but more likely it's something like an intertior light bulb that's on and you don't know it, or an electronic device that's on that you don't know about.
 

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you can do a parasitic draw test, its quite easy if you have a simple 12V test light. but as tom said ^^ go have your charging system tested at your local auto parts store. they will do it for FREE! (dont ya love that word?)
 

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disconnect the negative battery cable from the battery. withOUT your keys in the ignition, headlights OFF...NOTHING on in the car at all (door closed so interior light isnt on, etc) plug a 12V test light in series between the negative battery terminal and the negative battery cable.

the light should light up a LITTLE bit, it should be fairly dim. there will always be a little bit of parasitic draw from the battery to keep the ECU and radio memories in tact. if the test light is bright you have a large parasitic draw on the battery.

if the light is bright: start systematically unplugging fuses from the FRUNK fuse block until the test light goes out or goes DIM. when it does, whatever fuse you unplugged to make it do that is your problem circuit. if none of the ones in the frunk make a change in the light, move to the one in the engine compartment.

whatever you do, dont let the interior lights come on or turn on any accessories in the car. you WILL blow out your test light because it can only handle like 3 amps. just enough to test for parasitic draw. make sense?

i just noticed that your location says you are "just outside of DC". im over in centreville and dont have school today (friday) so if you need a hand, feel free to stop by my house or something.

hope that helps,
Doug
 

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Discussion Starter · #7 ·
Thanks for the info bro. I'll try it out.

and thanks for the help offer. I'm living in Gainesville now. If I need help, i'll let you know. Same goes for you too.
 

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Also check your battery and Make sure it is Clean. Too much dirt buildup on the top of the batter will act like a short.
 

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Discussion Starter · #10 ·
celicaguy13 said:
Also check your battery and Make sure it is Clean. Too much dirt buildup on the top of the batter will act like a short.
It's a brand new battery. looks almost new hahhaa. My car probably only got driven about 100 miles on the new battery
 

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I have the same problem. I have a new battery that I bought last year, it's a deep cycle Altima battery. I'm a student so I ususally take the campus shuttle to school during the weekdays and drive on the weekends. With my old battery, interstate battery, it would barely have enough power to start the car. But since I keep reviving it, I messed up the battery life so I got the Altima Battery. But now the battery would only last a day or two, enough to start the car, if more than 2 days I need to jump start it. I think its because before I went back home for winter break, the battery was really low so I jump started my car, and only let it run idle for 10 mins then I turned off the car and disconnected the battery and went home. Coming back from winter break, I reconnected the battery and I've only been putting like 10 or 15 miles on the car. Am I not driving enough to fully charge the battery? My friend said 15 miles is not enough to charge the battery.
 

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It could be just a bad battery you bought. If you have a spare battery try to see if that one drains. if that doesnt fix it then your going to have to do the parasitic test.
 

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Have you ever suggested a bad alternator? I bought my 91 MR2 from seattle (with a new battery) in 2004, and 6-7months later the battery was drained dead. the alternator was my problem.
 

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Discussion Starter · #14 ·
If your alternator was not working, then the car would run on the battery. This would drain the battery within a few hours of running.
 

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vtsuckah said:
If your alternator was not working, then the car would run on the battery. This would drain the battery within a few hours of running.
Oh believe me, it was running fine,...it must have just been in Dec.04-Jan.05 that the alternator went out on me. yeah, the battery did drain out pretty quick alright, as i was going downhill... :eek: w/ everything blacking out and locking up on me. fortunately, I was able to slow down into a gas station...but i know what you mean.. if the alternator's bad, the battery would also be dried in hours.
 

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Even though you just replaced a part doesn't mean it can't be the problem. When you have a electrical problem you should always check the main charging system components. (Exp. Battery, alternator, Terminals, Cables...) Trust me have the alternator and battery checked, at least then you'll know for sure it's not them.
 

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Discussion Starter · #17 ·
Well i did that draw test. The test light was bright for a split second then went dim and stayed that way. So that's fine. Went onto the frunk fuses........are the two headlight 15 amp fuses supposed to not light up when nothing is on? I touched the test light on both sides of each fuse and they and another fuse did not light up like the rest.
 

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the problem is the alternator. no recycle in power. u used up all your battery power. go rebuilt your alternator or buy a new one. it has nothing to do with your alarm.the best way to know if its your alternator is, try turning on the Emergency lights. doesnt turn on... its your alternator. if it does turn on then something is drain your battery, or something is wrong with the cables. usually wen u drive the asb would turn on if it was the alternator, or the cables. soo break it down. did your cars asb turned on? did the battery completly died out? its 1 of those #1 alternator (my guess) #2 cables.
 

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how would turning on emergency lights tell you if your alternator is bad or not? if ANY electrical accessories dont work, or the engine doesnt start, it doesnt necessarily mean you should just blame the alternator. If the alternator isnt charging, the battery light illuminates (unless the bulb is out :p ). He states in his original post that the battery only dies after the car has sat for 3 or more days- implying that the alternator IS indeed charging the battery, just that the battery is draining down somehow. Generally this is some sort of parasitic drain.

Whats the "asb"?

I would be careful quickly blaming the alternator as they are (a. very expensive and (b. Difficult to replace in an mr2.

he needs to get the system tested at a local store. they do it for free. im not saying that it COULDNT be the alternator.... just to be careful quickly condemning it!

Vtsuckah- i realize this thread is real old, but did you ever get this problem resolved? If not... did you try using an Ammeter to test for the parasitic draw, instead of a test light? They are a lot more accurate, and may help you more!
 

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Discussion Starter · #20 ·
Wow talking bout digging up old threads. hahhaa

no, I still haven't found the problem. Well I have, and I haven't. The problem is my alarm. As long as I don't have my alarm armed, my battery does not die at all. The two is in the garage all night/day so i really have no use to arm the alarm, until i take her out. Even then, the battery won't die in a matter of hours. But I still haven't been able to find where it's shorting out, nor have I even bothered since i've been doin other odds and end jobs.
 
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