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vchalupa

macrumors member
Original poster
Jan 24, 2008
77
0
Hey guys,

I've been having this issue and I've looked on a ton of forums and can't figure out what's going on but I do have some ideas.

So last week I was running a few applications and knew battery was CPU and laptop was running hot. I'm estimating that the CPU was at about 88ºC. I was basically trying to run down the battery for a battery calibration. All of a sudden, the laptop just shuts down without notice. I thought it was because the laptop overheated so I let it sit for a while and it seemed to be running just fine.

The same problem occurred today. I was running an antivirus scan and video chatting with a friend while the laptop was running on battery power like it was last time. And when the battery charge was between 20 and 30%, it just shut off. When this happened, I flipped the MPB over and saw that the battery was not on reserve power so I waited a few minutes and booted again and as soon as I logged in, it shut off again. So I waited a while for it to cool off and at that point I needed the laptop so I connected the power source and the laptop booted and was working perfectly fine.

Does anyone know what's going on here? Here are my guesses as to what it could be:

- Very poorly calibrated battery
- CPU force shuts down the computer because of overheat

Any help would be much appreciated. Thanks in advance
 
Yeah it does sound like a dead battery cell. My MBP suffered similar symptoms to yours, shutting down at around 20-30% power. If you have Applecare call them up for a new battery, if its under 80% health and under 300 cycles. Otherwise buy a new battery.
 
Yeah it does sound like a dead battery cell. My MBP suffered similar symptoms to yours, shutting down at around 20-30% power. If you have Applecare call them up for a new battery, if its under 80% health and under 300 cycles. Otherwise buy a new battery.

I guess this is where I lucked out. I'm at 69% health and 581 cycles. I've had the laptop for only a year and I knew the battery was pretty much butchered. So even though I have Apple Care, I don't think my battery is covered under warranty because of the number of cycles on it.

So if I dish out the cash to buy a new battery, then what's the warranty I'll get on that battery? Would it be one year, up to 300 cycles? Or would it somehow tie to my Apple care?
 
So if I dish out the cash to buy a new battery, then what's the warranty I'll get on that battery? Would it be one year, up to 300 cycles? Or would it somehow tie to my Apple care?

Typically they "guarantee" the battery will hold 80% of its original capacity for 1 year or 300 cycles, whichever comes first. After that you're on your own, and it's not covered under Applecare (batteries are classified as a "replaceable part" or some other stupid technical term).
 
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