Q: iMac won't wake up from sleep using keyboard or mouse

Sorry to hear that!, i can't see it being the PSU as when you boot the machine it will work fine? if so then the PSU is ok, some how putting the machine to sleep then trying to wake, power is not being sent to the backlight board, or its not being told to turn back on if you see what a mean? Not having the machine in front of me its really hard to diagnose, its also not the easiest machine to check with a meter when its working and when its not, that way you can be sure if power is there or not! if you don't activate sleep does the machine just work away as normal??

I am having the same intermittent problem. Sometimes wake up from Bluetooth keyboard / mouse works, sometime it doesn't. When it doesn't, even a wired USB mouse won't wake it. Nothing. Only power button to turn off and reboot works. Frustrating.

As i have not experienced this yet! then its hard to say, straight away i would say the bluetooth for the keyboard or mouse disconnects but people have tried wired keyboard also people say its sometimes not just a case of pressing the power button once but five,six times and in worst case, total reset.
As many of you may have read now another poster has changed many parts including the logic board! problems are still there ??? is this then OS X related??? i really don't know

Hello superman3gsm
How often does your iMac experience this sleep issue?
The reason I'm asking is that I unplugged my iMac the last time it happened (not waking from sleep) instead of using the off/on button. It's been several weeks since the iMac had this sleep issue.

Add me to the list, I have a 27" iMac from 2010 that sometimes won't wake from sleep via it's Apple bluetooth mouse/keyboard.

I'm having the same problem concerning my imac not waking from sleep. I bought my 27 inch imac refurbished from the apple store in October 2010. Sometimes it does wake from sleep and sometimes it won't and I have to turn it off by holding down the power button. I have not called apple yet. I cannot manually produce the issue by putting the machine to sleep. I am using the bluetooth mouse and keyboard that came with it. Does the imac have a deeper sleep mode after it sleeps for several hours?

Message was edited by: kasedogg

If it doesn't wake from mouse or keyboard, try to toggle sleep mode with CTRL-SHIFT-EJECT followed by RETURN. If that works then it is likely there is an issue with backlight board and it will need to be replaced.

Hi,

Having a problem with a 2 month old new type iMac 27" i7. SD and HD configured.
USB keyboard.
Wireless mouse.

Waking problems, intermittent. Screen wakes OK every time.
Keyboard OK.
Mouse..........no response.
Rebooted, and decided to configured an old Bluetooth mouse (backup) and realised that the original new mouse was NOT listed as a recognised device?
It is almost as thought the pairing info vanished!
If this happens, it just thinks the keyboard/mouse belongs to someone else and ignores them. This has to be a Mac OSX problem and not firmware/hardware issue.
Restarting the Mac and the mouse is OK...until the next time?

Mine is stuck in a frozen blue screen....lollipop and all. Dang it! I tried all the "secrets" also and now look. Good grief. And I just got mine for Christmas!

Dr. Green! You sound like me! I am freaking out...I just got this new iMac and I was scared to death that something fried it because a thunderstorm blew through our town last night. Turns out I was incorrect; all of these things are happening to other people as well. I turn on my computer and all I get is a frozen blue screen, and nothing else. I have tried everything you have just listed, to no avail. What now?

Hi kasedogg,

I had my new imac for about the 3 months now and it has the same issue. As this is my second imac, i pretty much "accepted" it, though I was hoping that being the latest mac the issue would have been fixed. Instead of spending time on it, i rather just enjoy the machine. As in my previous post I use a small utility call PleaseSleep and it works for me. But lately i found that it is working by itself even without the utility, so its sleeping and waking up fine! What I did do different is that I have set a password immediately when waking from sleep (system preferences -> security). So its either that or it has somehow healed itself, dunno.

Cheers

Have had this "won't wake" issue since last autumn (iMac 27" Dec 2009) but it occurs only once or twice a month and am unable to run down any common factors. I thought it was bluetooth initially as I use wireless keyboard/mouse, but even when swopped to wired I get the same problem. I have noticed that when it will not wake up it is warm on the top right so is not shut down, but have to reboot to turn on. Most frustrating but glad it's not every day and it would be nice to have a solution.

It's because the backlight board is defective and has to be replaced. Please take it into your local Apple repair centre and ask them to replace the backlight board.

From a conversation with a higher level advisor at Apple Care (800-275-2273) I performed the following:
First I installed the applications disc and ran the hardware test (hold down "d" key during start up) and found there to be no issues (with the backlight board, specifically).
Second I did a clean reinstall of the system which required doing something different than I had done before: erasing the hard drive.
a. backup on time machine
b. insert the Mac OS disc that came with your computer
c. shutdown then power back up holding down the "c" key to boot off the disc
d. hit return to use english
e. go to the top bar and click utilities, disk utility, click your Mac HD, click Erase, Erase, Erase and close the window
f. you are now back on the Install Mac OS X screen; agree; click your Mac HD and install Mac OS X
g. 30 minutes later OS X will be there and then you can load your stuff from Time Machine. (Select the item from Time Machine with the highest number if there is more than one version. It may give you two or more options if you have used the external drive for a prior computer. If you pick the one without "(2)" after the name of your drive--like I did--you kind of waste a couple of hours.)
h. finally, remember to go to settings and under bluetooth enable the wake mode for the mouse and keyboard. Initially I thought all was for naught as tapping the keyboard did nothing. But the wife knew about the bluetooth settings.

So for now, it looks like we are good. Really won't know until this does not happen for a week or two. The AppleCare super techie said this is currently his most common problem that he is dealing with and this method works 99% of the time. If so, wouldn't it be nice of someone from Apple, not some yahoo like me, was providing these instructions.

But you got them anyway.

I hope that works for you.

BG

I've got a 27 imac (late 2009). Have had this issue about once a month for over a year now and finally decided to call tech support today. (Very good service btw). I was told that drivers from Tiger may have made it over via my migrations as I've moved through my various iMacs and to do a clean install. Seems reasonable. I'm going to try when I get the next rev iMac with Thunderbolt or earlier if I have time.

So if you're having the issue, seems like you need to ask yourself the Tiger migration question. I'm also going to try the hardware test app the previous poster mentioned.