Mac Mini won't wake after sleep with Mountain Lion
I have a late 2012 Mac Mini with Mountain Lion installed. I have had the Mini for around 6 weeks and am using as a media server.
When the Mini goes to sleep (either automatically or by manually telling it to) it refuses to wake up. The power light is pulsing.
The Mini is connected via HDMI to a home cinema receiver (which is in turn connected to a TV) and has an external USB hard disc and USB hub attached. There is a wireless keyboard and mouse attached via USB also.
In the Energy Saving preferences I have all tick boxes enabled apart from "put hard discs to sleep". I have tried the wireless keyboard, mouse and the Apple Remote app to wake the Mini to no avail.
Any ideas? I really need it to sleep and wake when needed as thats an essential feature of a media server.
Try resetting the NVRAM / PRAM as noted About NVRAM and PRAM
Resetting NVRAM / PRAM
- Shut down your Mac.
- Locate the following keys on the keyboard: Command (⌘), Option, P, and R. You will need to hold these keys down simultaneously in step 4.
- Turn on the computer.
- Press and hold the Command-Option-P-R keys before the gray screen appears. Hold the keys down until the computer restarts and you hear the startup sound for the second time.
- Release the keys.
See if the sleep problem still occurs, if it does try resetting the SMC as noted Intel-based Macs: Resetting the System Management Controller (SMC).
Resetting the SMC for Mac Pro, Intel-based iMac, Intel-based Mac mini, or Intel-based Xserve
- Shut down the computer.
- Unplug the computer's power cord.
- Wait fifteen seconds.
- Attach the computer's power cord.
- Wait five seconds, then press the power button to turn on the computer.
If the problem still persists and you are running OS X Mountain Lion version 10.8.2, there may be a sleep bug that is effecting the reliability of sleep on a lot of Macs as discussed Problem with waking from sleep with 10.8.2
My Mac Pro (early 2009 2.66 GHz Quad-Core Intel Xeon) won't wake from deep sleep after installing OS X 10.8.2 . I have the default setting set for sleep. The only way to "wake" the machine is to hold the power button down to shut down and then restart. I've reset NVRAM (pram) and tried removing power cable. Nothing helps.
Since your Mac Mini is very new I would also consider contacting Apple Support and see what they offer as a solution and at the least notify them of the issue, I am sure they are working on a fix probably scheduled to be included with the next OS X update.
Mac Mini / monitor problem SOLUTION! (I think)
I think I found the solution to the great Mac-Mini monitor that won't wake up after sleep problem, at least for an HP 2159m monitor and my Mac-Mini 5.1 --but probably for many Mac/monitor combinations. It appears to be just a simple timing problem between components. it has nothing to do with Mac firmware, NVRAM / PRAM or anything more exotic, it has to with how fast the Mac Mini comes online vs. the monitor itself.
Many monitors have a default setting to accept either VGA, DVI or HDMI or autodetect the input. Typical factory default monitor settings are to try to autodetect the input and, if no signal is detected, to default to VGA. My theory was that the monitor autodetected and defaulted before my Mac Mini fully started sending its HDMI signals.
My solution was to set the monitor (with the monitor's controls) to default to HDMI rather than VGA. After I did that the problem disappeared, now it wakes faithfully every time. Because it is expecting HDMI signals the Mac-Mini can take as long as it wants to start sending them.
The Mini may not actually be asleep, instead the screen may just be deactivated.
I am seeing similar issues in my 10.8.3 Mini so I enabled remote ssh login.
I could remote login and run commands while supposedly the Mini was asleep.
I'll keep digging to try and find the root cause.
Problem potentially fixed!
Progress bar appears after waking from sleep.
It is the new Safe Sleep feature.
To disable it:
- Go to terminal
- Type:
sudo pmset -a hibernatemode 0- Enter your password when prompted
- Type
sudo rm /var/vm/sleepimage- Reboot
According to AppleCare, use sudo pmset -a hibernatemode 3 to reactivate Safe Sleep.