Please help! Macbook pro randomly turning off when not plugged in, have new battery

Discussion in 'MacBook Pro' started by danabean, Mar 4, 2013.

  1. danabean macrumors newbie

    Mar 4, 2013
    I have a late 2008 (2009?) Macbook Pro that I bought used. It worked fine hte first year, but the battery slowly started getting worse and worse, until it would only last unplugged for maybe an hour before it got drained. So I purchased a new battery.

    I installed the battery without any problems and the 'Service Battery' message is gone. The battery says normal, see below.

    If I unplug the charger, the macbook will keep working, nothing weird happens. But usually after 20 mins or half an hour, it will just turn off with NO warning. There is no warning for low battery either if it happens to get down near 10-15%, just black screen. Laptop starts just fine once plugged back into the wall. The time it takes to turn off varies.

    WHY IS THIS HAPPENING? WHAT can I do to fix it? This is a brand new battery.

    Battery Information:

    Model Information:
    Manufacturer: SMP
    Device Name: bq20z95
    Pack Lot Code: 0
    PCB Lot Code: 0
    Firmware Version: 0
    Hardware Revision: 0
    Cell Revision: 0
    Charge Information:
    Charge Remaining (mAh): 2100
    Fully Charged: No
    Charging: Yes
    Full Charge Capacity (mAh): 4133
    Health Information:
    Cycle Count: 29
    Condition: Normal
    Battery Installed: Yes
    Amperage (mA): 2163
    Voltage (mV): 11769
  2. GGJstudios macrumors Westmere


    May 16, 2008
    Have you calibrated your battery? Instructions for doing so are in the CALIBRATION section of the Battery FAQ linked below.

    You could also try resetting the SMC.

    Hopefully, you bought a genuine Apple battery. I wouldn't trust or recommend any non-Apple battery, due to the number of problems reported with "knockoff" batteries. Also, there is no assurance that knockoff batteries have the same charging technology that Apple uses, involving the battery, the MagSafe adapter and the Mac's logic board.

    The link below should answer most, if not all, of your battery/charging questions. If you haven't already done so, I highly recommend you take the time to read it.
  3. danabean thread starter macrumors newbie

    Mar 4, 2013
    Thank you. I will try calibrating and resetting the SMC and re-post later on if there has been a difference in performance
  4. GGJstudios macrumors Westmere


    May 16, 2008
    On models with removable batteries, you should be calibrating every month or two.
  5. tonupi macrumors newbie

    Mar 28, 2010
    i have a similar issue,
    but when the mac power off, i have to push twice the the power button, to switch on the mac on.
    aftrer the first push i see the light power flash once.

    does this happen also to you?

    thank you
  6. danabean thread starter macrumors newbie

    Mar 4, 2013
    There is a problem with says to run down the battery after charging until it's at a very low level...but THIS is the problem. It will never make it that long, because it will have turned of once or more during that time before it can make it down to 10%..........
    so how am I supposed to calibrate then.....
  7. GGJstudios macrumors Westmere


    May 16, 2008
    Just let it run on battery until it powers off, regardless of the percentage. Then leave it on battery for at least 5 hours more before you plug in again.

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