Macbook just shuts off at 25%, no warnings at all.

Discussion in 'MacBook Pro' started by Star Destroyer, Mar 18, 2007.

  1. Star Destroyer macrumors 6502

    Joined:
    Jun 15, 2006
    #1
    Hey all,
    This is really quick, but its really pissing me off. My macbook 1.83 CD 1 GB ram has been running off battery lately and when the battery gets to about 25% (or around 50minutes remaining depending on settings) it will just shut off, no warning signs, no beeps, NOTHING. One minute i was working on some reports then next minute the screen is black and it had powered off. This has happened twice now. When i did my battery calibration it gave me a warning and went to sleep, but now all of a sudden its just shutting off. I am losing work, and hours of it! How can i fix this? I assume there is a setting i should change, but where?

    Thanks!
     
  2. amacgenius macrumors 68000

    amacgenius

    Joined:
    Aug 3, 2005
    Location:
    Buffalo, NY
    #2
    I had this happen with my MacBook for the longest time, the only solution it to take it to an Apple Store, and a Genius will give you a new battery on spot after you explain your problem, granted my battery had to be ordered because they didn't have any Black batteries, you should be in and out.

    The Genius didn't really tell me why this happens because he had never seen it before so I can't really answer as to why, but I can tell you what to do.

    :)
     
  3. iBenzin macrumors member

    Joined:
    Mar 9, 2007
    #3
    Take it to the Apple Store and have that battery replaced.
     
  4. Star Destroyer thread starter macrumors 6502

    Joined:
    Jun 15, 2006
    #4
    I posted here because i am canadian, i dont have an store withing 4 hours of me. I called apple support and they told me that it did not meet the critirea for a replacement after asking me my cycle count, and charge remaining... He said there was nothing he could do, i also reset the PMU and the PRAM and everything. It just shuts off on a low battery, it gets to that 25-30% remaining and it just dies, when i first calibrated it it went to sleep after giving me a warning and would sleep for hours before it died.
     
  5. iBenzin macrumors member

    Joined:
    Mar 9, 2007
    #5
    Talk to a supervisor. Dont take no for an answer.
     
  6. Star Destroyer thread starter macrumors 6502

    Joined:
    Jun 15, 2006
    #6
    Is there a setting i can change? somewhere that asks like "Display low battery warning before sleep ?" or something, maybe i just have the wrong thing checked off?
     
  7. a1291762 macrumors member

    Joined:
    Aug 19, 2003
    Location:
    Australia
    #7
    Have you calibrated your battery recently? Battery output changes over time and the machine has to guess at the remaining power based on the battery's output. Your machine thinks your battery has more power based on the last calibration. Calibrating again should correct this.

    You might want to try an app like coconutBattery to get a report of your battery's performance.

    Note that cold weather will temporarily drop the battery's output. I got freaked out one morning because coconutBattery told me my battery had 60% of it's capacity left but once the machine warmed up it went back to normal.
     
  8. Star Destroyer thread starter macrumors 6502

    Joined:
    Jun 15, 2006
    #8
    Yeah i have calibrated my battery, but if i try again wont it NOT work? I thought to properly calibrate it you have to let it fully drain the battery, and it goes to sleep, then you let it sleep until it shuts off then let it sit for hours before recharging. With mine the battery doesnt get used all the way up, it says i still have 50 minutes remaining then just shuts off. This doesnt seem like it will ever ALLOW my battery to fully drain, right ? therefore no more calibration ?

    See the pickle i am in!? hahah

    Its all of a sudden a problem because i lost about 2 hours of work (ya i know savesavesave!) but i was wasnt paying attention and thought i has an hour left, then bam, black screen..
     
  9. a1291762 macrumors member

    Joined:
    Aug 19, 2003
    Location:
    Australia
    #9
    No. The problem is the other way around. Your computer thinks you have more capacity than you actually have (since it's estimating time based on a previously recorded output curve) so it doesn't shut off early enough. My machine used to do this when it was new, especially when running Windows. The Li-Poly batteries that Apple uses can take a little while to settle in and may need recalibration several times. Apple recommends recalibrating every 2 months!

    When you calibrate the computer you give it a chance to monitor the output of the battery from full to empty. This will let it revise it's estimates to match what your battery is actually doing.

    So follow the instructions to calibrate your system. Don't worry that your computer is turning off instead of sleeping at step 4, just keep going.
    http://docs.info.apple.com/article.html?path=Mac/10.4/en/mh2339.html
     
  10. mopppish macrumors 6502

    Joined:
    Nov 27, 2005
    #10
    I had the same problem with my C2D MBP. Calibrating it didn't work. I think it's a problem with the battery's internal sensors. Regardless, when I called Apple about it, they offered to replace the whole laptop, which I took them up on because why the hell not?
     
  11. MaaseyRacer macrumors regular

    Joined:
    Oct 30, 2005
    Location:
    San Francisco, Ca.
    #11
    Try a calibration, run the computer completely down to empty from a full charge. leave it off for 5-8 hours completely dead, then charge is straight uninterupted for about 12 hours. After that do the power management reset.
    http://docs.info.apple.com/article.html?artnum=303319
     
  12. Cole Slaw macrumors 6502a

    Cole Slaw

    Joined:
    Oct 6, 2006
    Location:
    Canada
    #12
    Lately my 10 month old Macbook's battery has been doing the same thing.
    When I'm running it on battery power it would shut down (not sleep) at about 18% or so remaining power.
    I have been calibrating the battery and I tried resetting the PMU, but it didn't help.
    I called Apple and they are sending me out a new battery.:)
     
  13. smearedblue macrumors member

    Joined:
    Mar 7, 2005
    #13
    same thing just happened to me.. my battery has only been cycled 14 times.. and when i updated to 10.5.2 i noticed some serious power issues.. and now it discharges really fast, and when it gets to 48%, it just shuts completely off.. and when i turn it back on it's got 55% charge.. so i checked the health of my battery since it was at 99% a week ago.. (istat) and now the health is at 60%.. what's the deal.. i'm taking it in in an hour..
     

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