Mountain Lion won't wake from sleep

Yes, looks like Mountain Lion's hibernation is the one that's preventing it from waking up. Disabling hibernation should do the trick – although obviously this isn't a long-term solution and it reduces battery life as I travel (I usually don't shutdown the Air).

No, there isn't any Facebook Chat app installed in my Mac.

SOLUTION for SSDs machines.

For those of you with 3RD party SSDs, this solution worked for me.

Update the firmware on your SSDs, after 10.8 something screwy happened to where the mac would not be able to communicate with the SSD, making it freeze and have to do a forced reboot. Manufacturers like OSZ and Sandisk, addressed the issue in seperate firmware updates. I just updated mine and after testing with sleeping for both 20mins and 8 hours, the freezing issue has stopped. Hopefully, this will help others as well.

Go to the manufacturers website for your SSD and update to its latest SSD firmware, reboot and it should all be better now. Goodluck!

Still not fixed in 10.8.2.

So is disabling deep sleep the only option?

I noticed the other day that my MacBook Pro 2010 has been sitting for days with the lid closed and the power light is still turning on and off. In other words, back then, when I first got it new, it had the same problem, and I disabled the deep sleep / hibernate / standby. I don't know if they ever fixed it for MBP, but it is amazing that the same problem exists in MBA.

Even light sleep does not work for me.. I tried hibernatemode 0, 3, 25 and I believe another one, all without a good result. Now I shutdown my laptop at the end of the day.. I can't believe it's still not fixed in 10.8.2...

But mine fixed on 10.8.2...I also removed some crap softwares. Not sure which one resolved the problem

10.8.2 and the EFI firmware update did not fix my mid-2012 MBA, either. Not only that, the new iPhone beach balls and crashes. The MBA fan comes on a lot, whereas it didn't before. I know, time for more email to Apple.

10.8.2 and the EFI firmware did fix it for me on my rMBP. Your mileage may vary. 🙂

So, mine is fixed. I now have hibernation mode set to -3, and sleep is functioning perfectly. -25 works too, but is a bit to slow to wake for my taste.

I have noticed a HUGE improvement in battery life since 10.8.2. It was good enough for me before. Now it's way better.

Okay, here was my fix- I went into Systen Preferences, Desktop & Screen Saver, then selected the Screen Saver Tab and scrolled down to Screen Savers and selected iTunes Artwork... Now, I do not have a clue why this worked, but it did - Im assuming it has to do with the "sleep mode" asscociated with each saver?

Anyway, hope that helps someone...

I had the same problem with my mbp 2009 version since I upgraded to mountain lion from snow leopard last week.

I tried all of the solutions offered in this forum and none worked for me.

I spoke with apple customer service last night and they told me to go to system preferences / energy saver and then to deselect "put hard disks to sleep when possible".

They also told me to do a pram reboot by pressing 4 keys alt/option / command / p / r at start up to clear my ram.

Good news, my computer woke up nicely after being left on overnight. So it looks like the problem is solved. I suspect the deselecting the put hard disks to sleep is all that was needed so that should be step 1 since the pram reboot is not recommended.

I hope this helps those that are frustrated by this problem as I was.

I posted a sollution for this problem in this thread:

https://discussions.apple.com/thread/4150333?answerId=19958728022#19958728022

I encountered this problem too. Deleting the Power Management pref file seemed to have fixed it for me:

/Library/Preferences/SystemConfiguration/com.apple.PowerManagement.plist

Finder > command + shift + G > paste the above path, delete the file and restart your Mac. Let me know if this helped for you.

Unfortunately this didn't work for me.. still the same issue.

My wake problem is solved. In my case the problem source was pinnacle dazzle DCV100 connected to my Imac. 5 days with no problem, using all options of power management (sleepling disks and wake from lan) and with sleep and wake programing (sleep at 0:00 an wake at 7:00).

All other things connect are woking well and do not interfere with sleep/wake (firewire disks - iomega 1Tb and seagate 500Gb, Pantone Huey pro, Targus USB powered HUB, TomTom gps dock, Bamboo pen and touch, iphone dock and Griffin Imic sound interface).

I have instaled OSX 10.8.2 in my macbook air and it's ok Today i will try in my wife and daughter (early 2009 and mid 2010) macs mini.

I am running OSX 10.8.2 Imac 27 inch late 2009.

For me the problem was fixed with http://support.apple.com/kb/DL1609 MacBook Air and MacBook Pro Update 2.0