3 Replies Latest reply: Apr 22, 2010 3:05 PM by Geoff Mathews
Geoff Mathews Level 1 Level 1
My machine is approximately 2 months old. Yesterday it began shutting down when I put it to sleep. Please advise

MacBook Pro 13 inch, Mac OS X (10.6.3)
  • Mac Medic (be@MacOSG.com) Level 6 Level 6
    Note the exact time the issue happens and check your System logs in your Console application for clues to the cause.

    Check out the new remodeled MacOSG website! 24-hour Apple-related news & support.
     MacOSG: An Apple User Group  iTunes: MacOSG Podcast  Follow us on Twitter: MacOSG

  • Tim Campbell1 Level 3 Level 3
    Check to see if your sleep mode has changed. See this article:


    (It's rather old, but it's still accurate for OS X 10.6 sleep modes)

    To summarize, open a "Terminal" window (in the Utilities folder) and type "pmset -g" ('pmset' manages power management settings) This will display your current settings.

    Check the 'hibernatemode'. The default mode is '3' for laptops. If your Mac is using anything other than 3, then this could be why it seems to just power off (especially if you are set to mode 1 or 5 -- which will completely power off the system after saving the state of RAM to a hard disk file.)

    If you are not using mode 3 and want to return it to mode 3 then type the following command in the Terminal window:

    sudo pmset -a hibernatemode 3

    You must have administrative permissions on the mac (a non-admin account can't make this change) and you will be prompted to type your login password.
  • Geoff Mathews Level 1 Level 1
    Thanks. It's set on 3. Haven't had the problem today. Normally my system updates on Friday. I updated yesterday morning.