5 Replies Latest reply: Dec 28, 2013 7:57 PM by Karbon
Karbon Level 2 (285 points)



This is regarding the Macbook Pro's actions when the battery drains completely ('06 - '08 that I know of). In older Powerbooks, the mac would just go to sleep when the battery had drained. With the MBP's (running 10.6 or 10.7), the machine shuts completely down - losing anything not saved, and requiring a full restart and opening of all my work again. I've been reading through  other posts on this topic and tried various solutions posted, but nothing has changed. Has anyone found a consistent solution I've missed?


It doesn't have anything to do with "Restart after power failure" being selected as someone suggested. I've always had that selected on both laptops and deskstops since forever, and it's not relevant.Also, zapped pram, reset SMC (tried the one for unibodies as someone suggested, but no change), etc, etc.


I'm on a MacBook Pro early 2008 (A1260) running Snow Leopard. It also was happening on my niece's MacBook of the same year running 10.7.x. I do have a new replacement battery installed, not a cheapie one, but not an apple one either. It has been working fine, no issues though - is lasting for 3 - four hours depending upon what I'm doing. This is very dissappointing if it's going to be the way Apple laptops are going to handle battery calibration (or just normal usage while on battery charge). I've always trusted my Mac to take care of business when in such situations, and leave me high and dry like it is now.



Mac OS X (10.7), iMac 2006 24" / MBP '08 / ETC / ETC
  • SwankPeRFection Level 4 (1,435 points)

    This is the default behavior when Standby isn't enabled on a Mac.  The system will NOT "Sleep".  Sleep mode requires that the RAM be powered up in order to maintain a current snapshot of what's running on the machine.  By default, the system will wake up at I think 5-10% battery and shut itself all the way down.  If the hibernation mode is set to 3 and you enable Standby, this shutdown should not happen.  These settings are all changable and verifiable via the PMSET command in Terminal.

  • Karbon Level 2 (285 points)

    But since when? I have never had to enable anything via Terminal or anywhere else before - it's always been default behaviour. I've been using Macs since the early nineties. And have worked on pretty much every model made up to the 2010 models and every operating system.  I did run the pmset command in Terminal earlier though, and I'm quite certain that hibernation mode was set to 3 - not sure about Standby being enabled - and not sure how to do it either. One of the reasons I use Macs, not peecees, is because I'm not really interested in having to program a computer do a job it's always done before, lol. Sleep settings for both display and hard drive have been set in the Energy Saver preferences - but those settings have never been associated with the battery's discharge settings before.


    Do you know how to enable the standby mode via terminal? And thanks for your input.

  • SwankPeRFection Level 4 (1,435 points)

    You said "old Powerbooks".  That's completely different hardware than the MBPs you have now.  Unless you're going to tell me that your MBP (when you got it) behaved that same way and you've done no updates to its software that could have changed this behavior, etc. then you're not comparing Apples to Apples. (yes, pun intended).


    sudo pmset standby 1 to enable standby, but before you do that, do a pmset -g and copy/paste the results into a post on here.  Let's see what you have right now before we go changing things needlessly.

  • Karbon Level 2 (285 points)

    Hi again. Sorry for the very long delay - the mac went splatt for a while and I'm just getting it back up and running now.


    I did what you suggested - here are the results of typing "pmset -g"...


    Active Profiles:

    Battery Power        -1

    AC Power        -1*

    Currently in use:

    lidwake    1

    autorestart    1

    halfdim    1

    sms        1

    hibernatefile    /var/vm/sleepimage

    disksleep    10

    sleep        30

    hibernatemode    3

    ttyskeepawake    1

    displaysleep    15

    acwake        0

    womp        0


    [Process completed]

  • Karbon Level 2 (285 points)

    I have been going through other posts regarding this and found this Apple article that confirms that the MacBook Pro like my "old" Powerbook (the model listed below and all powerbooks before it) should indeed go to sleep when the battery is drained...


    PowerBook G4 (15-inch Double-Layer SD), MacBook (all models), and MacBook Pro (all models)

    The battery calibration for the PowerBook G4 (15-inch Double-Layer SD) and any model of MacBook or MacBook Pro has been updated because of a new battery released with this computer. With these computers, follow these steps to calibrate your battery:


    1. Plug in the power adapter and fully charge your PowerBook's battery until the light ring or LED on the power adapter plug changes to green and the onscreen meter in the menu bar indicates that the battery is fully charged.
    2. Allow the battery to rest in the fully charged state for at least two hours. You may use your computer during this time as long as the adapter is plugged in.
    3. Disconnect the power adapter while the computer still on and start running the computer off battery power. You may use your computer during this time. When your battery gets low, the low battery warning dialog appears on the screen.
    4. At this point, save your work.  Continue to use your computer; when the battery gets very low, the computer will automatically go to sleep.
    5. Turn off the computer or allow it to sleep for five hours or more.
    6. Connect the power adapter and leave it connected until the battery is fully charged  again.


    Tip: When the battery reaches "empty", the computer is forced into sleep mode. The battery actually keeps back a reserve beyond "empty", to maintain the computer in sleep for a period of time. Once the battery is truly exhausted, the computer is forced to shut down. At this point, with the safe sleep function introduced in the PowerBook G4 (15-inch Double-Layer SD) computers, the computer's memory contents have been saved to the hard drive. When power is restored, the computer returns itself to its pre-sleep state using the safe sleep image on the hard drive.