I have this strange problem with my early-2011 MacBook Pro, running on OS X 10.6.8: as of a month or so, sometimes it does’t wake up from sleep unless I press the power button for a longer period (5-10 seconds). However, when I do that, it starts waking from hibernation (the grey screen with the progress bar appears) and then it restarts. Usually the battery shows half full, so theoretically it shouldn’t go into hibernation.
Anybody else running into this problem? How did you solved it? (I should mention that upgrading to Lion or Mountain Lion is not an option, so please don’t suggest that.)
Best Answer
It sounds like your battery is in bad shape. Your MBP goes to sleep and when it runs out of juice it simply dies.
If that's not the case - meaning the battery got's juice after a hard reset (holding power button for 5+ secs) without hanging to power supply then: First check if there are any Firmware updates. Then try the following:
Open up a Terminal in /Applications/Utilities/Terminal and to disable hibernation type:
sudo pmset -a hibernatemode 0
then remove any trace of previous hibernations:
rm /private/var/vm/sleepimage
After that reset the SMC aka System Management Controller:
MBP with removable battery:
MBP with non removable battery:
The LED on the MagSafe may change states - if so it means your SMC reset was successfull. To enable Safe Sleep again open Terminal and
sudo pmset -a hibernatemode 3
. Hope that help's.Update To have total control of Sleep try this http://semaja2.net/insomniaxinfo