Battery drops from 80% to 0%

hubristol

macrumors regular
Original poster
Nov 28, 2005
102
0
Hey, gang

I just got a Rev A Powerbook (TiBook). Everything on it works great, but I've been experiencing some problems with the battery. When it gets to around 82% or so, the computer shuts off / goes to permanent sleep until I plug the power cord back in. When I do so, it can be activated but the battery display says that it's at 0%. This has happened a few times now - every single time the battery drops to about the low 80s/high 70s. Has anyone experienced this? Is it a problem with the battery or the problem with my settings? I've downloaded coconut battery and it reads the battery strength exactly the same as the system itself does.

I just don't want to run into a situation where I'm taking notes in class only to have my computer shut off until I can reach the nearest outlet. Thanks.
 

tedrjr03

macrumors regular
Feb 9, 2006
174
0
My guess would be that it has someting to with the battery itself and not your settings.
 

hubristol

macrumors regular
Original poster
Nov 28, 2005
102
0
tedrjr03 said:
My guess would be that it has someting to with the battery itself and not your settings.
although I expected to hear this, I'm still bummed if this is true. I really don't have the $ to drop on a new battery especially seeing as how the battery itseslf would cost almost a third of what i paid for the laptop itself.
 

hubristol

macrumors regular
Original poster
Nov 28, 2005
102
0
mad jew said:
It's kinda sounding like a bad battery. This is quite a common way for them to go out. :(

Calibrate the battery as forrest1992 suggested and then maybe reset the PMU too. :)
Does it matter that coconut battery says that the battery life still has 87% or so of it's total life on it? I guess it would be closer to 20% or so? Would that just be a miscalculation on its part?
 

Makosuke

macrumors 603
Aug 15, 2001
6,163
346
The Cool Part of CA, USA
hubristol said:
Does it matter that coconut battery says that the battery life still has 87% or so of it's total life on it? I guess it would be closer to 20% or so? Would that just be a miscalculation on its part?
Until you run the calibration routine mentioned above, Coconut Battery only knows what the battery is telling it, so it'll be just as wrong as the menu. In theory, when you run a calibration, it makes that number more accurate, so Coconut Battery will report more accurately, and the percent meter will go down at a more even pace.
 

hubristol

macrumors regular
Original poster
Nov 28, 2005
102
0
Makosuke said:
Until you run the calibration routine mentioned above, Coconut Battery only knows what the battery is telling it, so it'll be just as wrong as the menu. In theory, when you run a calibration, it makes that number more accurate, so Coconut Battery will report more accurately, and the percent meter will go down at a more even pace.
I did this but it still shows the incorrect reading. I contacted the buyer to see if he may be willing to exchange my battery for another TiBook one (if he has one) since he probably wasn't aware of this problem (from the pics, it looked like he used it in a stationary, plugged in position most of the time).
 

Makosuke

macrumors 603
Aug 15, 2001
6,163
346
The Cool Part of CA, USA
hubristol said:
I did this but it still shows the incorrect reading.
Chances are the battery is just old and worn out--there's really not much you can do about this.

You might try a couple of full discharge-charge cycles--sometimes that properly re-calibrates the battery's processor, but it's just a maybe.
 

elbirth

macrumors 65816
Jan 19, 2006
1,154
0
North Carolina, US
Answer- The battery is essentially dead. There's no two ways about it and all the talk and bargaining in the world won't make it any less faulty, sorry.

My Revision A MacBook Pro's battery did the exact same thing, except it happened after it hit 95%. I calibrated by battery the day I got it and everything... but sure enough, after a couple months of having it, the battery went out and had to be replaced. Luckily mine was under warranty.

Just check around eBay and see if you can find one... or, see if it fits the current recall Apple has on PowerBook G4 batteries... if so, they should replace it.
 

bbergie

macrumors regular
Jul 3, 2006
213
0
Calgary
My immediate reaction after reading your original post is that you need a new battery. My TiBook's battery demonstrated the exact same symptoms when my battery was about 3.5 years old. I've since replaced it.
 

hubristol

macrumors regular
Original poster
Nov 28, 2005
102
0
Hey thanks guys...it's nice to know definitively what's wrong with it. I went ahead and purchased a used TiBook battery off eBay (at the moment, I couldn't afford a new one) that supposedly runs for at least three hours. Hopefully I won't run into the same problem with this new one.

Thanks again. I'll just have to make sure I sit next to the power outlet in my classes. :D