OS X 10.8.3 decreases battery life when in sleep mode (non PowerNap)

Discussion in 'OS X Mountain Lion (10.8)' started by ScratchSF, Apr 9, 2013.

  1. ScratchSF macrumors newbie

    Apr 9, 2013
    Wondering if others are experiencing a small / subtle problem I am observing on 10.8.3 where the batter life and battery health both drop after awaking my 2011 13" MBP from sleep mode (after it has been sleep for at least a few minutes); after it has entered sleep mode either due to the time trigger (located in Energy Saver) or due to the lid being closed?

    The concern is that this happens each time it goes to sleep; with a drop in battery health. Which means if I have it sleep 4 times before I charge it, the battery health will drop (so far by small amounts - e.g., .2 mAh to .5 mAh) each time. So, the concern is that it will eventually eat away at the overall battery health.

    This behavior occurs if the machine is on battery power OR on AC. It have also tried it with the Hibernate setting at 2, so that the computer would not try to keep power flowing to the RAM while in sleep mode. Since this is a 2011 MBP, it does not have PowerNap, so that shouldn't be a factor.

    This behavior did not occur on SL or on Lion. Trying to understand if this is a ML issue or perhaps something I can address on my end. So, hoping someone else has experienced this and possibly has a cure. Again, key point is that this was rock-solid on Lion, so this behavior is specific to ML.

    In the meantime, I have set the sleep mode to Never, although it will still sleep once the lid is closed.
  2. satcomer macrumors 603


    Feb 19, 2008
    The Finger Lakes Region
  3. ScratchSF thread starter macrumors newbie

    Apr 9, 2013
    Problem Potentially Solved

    My MBP does not have PowerNap capabilities. However, I'm currently doing an experiment to see if my problem has been resolved. I've used OnyX again to repair the disk and clear out the System and User caches. I'm hoping that has resolved it.
  4. benwiggy macrumors 68020

    Jun 15, 2012
    You can't repair the DISK with Onyx.
    You need to boot to another volume, such as the Recovery Partition, run Disk Utility and Repair the DISK.
    NB: Not Repair permissions, which usually does very little.

    Mac laptops have two modes: sleep and standby. Sleep maintains power to the RAM, keeping the data there. Standby writes the contents of RAM to the hard drive and shuts off most things, using less power.

    You can check and alter the settings of your Mac with the Terminal command pmset.
    "pmset -g" will show you the current settings.
    You need to run pmset with sudo to change values: "sudo pmset"....
    Read "man pmset" for more information.

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