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Discussion Starter · #1 ·
So i bought this car 6 months ago and it had a new battery in it. A couple months ago it kept going dead and i would need a jump and then it would go dead in another week unless jump started. Took it to get a new one and it tested good still. Got a new battery anyways. Same problem started happening after 2-3 weeks. It would go dead, i would get a jump start and it would last a week and go dead. Took it into the shop, they said the alternator was giving out a charge and only thing they found wrong was that the battery had a bad cell. I knew this wasnt the problem. So i basically paid them $86 to learn nothing. I returned the battery which was probably good and got a new one. Well its been 2 weeks and this battery is doing the same thing. So it seems like my battery isnt getting charged even when the car is running is my guess. Even tho they said they found no problems with the alternator im assuming this is the problem and i am getting a new one put in and hoping to end this never ending nightmare. Any advice on it being something else?? I would really appreciate it.
 

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I'm not an expert, but I have worked at an auto parts store, and do mechanic work for a living. These things are hard to diagnose over the internet. but i'll try :)

When you mean that the battery was dead, Headlights did not work?
or just that the car wouldn't start?
If the head lights were dim, then it has something to do with the charging system or something draining the battery down.

If the headlights were bright and it just wouldn't start, it could be any of the starting system (starter, etc) when it does start (without a jump) does it start easily or does it struggle a bit? I have seen starters pull enough juice that most batterys would not be able to get it to turn over, sometimes needing a jump to get it to turn over. also a possiblity that the starter solenoid may have bad contacts or bad connection also.


Assuming it has something to do with the charging system , I would first look at the battery terminals and cables. Make sure they are clean and there is no corrosion inside the cables. Feel the cables for lumps or see if it is still flexable. You might have to peel back some of the insulation away from the battery terminal. (make sure to tape the cable back up with plenty of electrical tape)

Check the termination of all the cables that go to the battery- ensure everything has a good clean connection (both ends of the cables)

Other than that, only other things i can think of to check would be the possibility would be a faulty voltage regulator or an accessory (radio, glove box light, trunk light, under hood light, etc) drawing power when it shouldn't be on. Voltage regulators are set to charge the battery depending on voltage. A fully charged battery should read at least 13.5v. With the car running, the Alternator should be charging at approx 14v. If the regulator is sensing that the battery does not need charged, it won't charge the battery. If you have a digital volt meter, measure the battery voltage with the car not running, and then while it is running... this will tell you if the alternator is even trying to charge the battery. I have seen regulators work intermittantly also..


lemme know if you find anything
 

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Discussion Starter · #3 ·
It will struggle to start about 3-4 starts towards the end of the week then it evenually wont start at all. Its been tested for drains and there were none found, but i dont think theres a drain because i started my car and let it run for about 5 minutes and came back a couple hours later and it wouldnt start. So it seems like the battery just doesnt get recharged. Only when i get it jump started it will recharge and last about another week. Headlights do go dim i think. Thanks for reply.
 

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I had the same problem with my 89. After you get the battery charged up again, go into the car at night and look for something lit that shouldn't be. Mine was a vanity light under the sunvisor that wasn't turning off. Hope this helps.
 

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Discussion Starter · #5 ·
No, theres no lights on inside. Dont even have vanity lights. The dome light stays on so i had to take that out a long time ago. When i took it to the shop they said they couldnt find a draw coming from anywhere. Thanks for the help tho.
 

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OK check for proper charge voltage with a heavy load on the alternator. Is it OK??? Then charge the battery and disconnect the neg cable every time you shut the car down at night. If it starts with the cable removed for a couple of weeks you have a draw down. That is the easiest way for an amateur to shoot a draw down. If you have a test light put it in series with the Negative battery cable. Shut the entire car down and look for the test light to see if it is drawing down. Is it on or lit dim or pulsing. If it shows any of these conditions you have a draw down. But first check the alt and drive belt for slipping. And make sure the battery is good ETC. I think you have a week alternator or a slipping belt. Checking the charge voltage will tell you the story. Good luck :bigthumbsup:bigthumbsup
 
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