Apple Event: May 7th at 7 am PT

Looks like no one’s replied in a while. To start the conversation again, simply ask a new question.

My iMac 27" screen won't come on after sleep mode,

the fan comes on really loud and just stays running with no screen start. I have turned it off and switched the plug off for the night and come back in the morning and it boots up fine... But then it goes to sleep and the same thing happens again?


I also recently updated the lion OS to the latest version available?


Please help...

iMac, OS X Mountain Lion (10.8.1)

Posted on Dec 19, 2012 3:57 PM

Reply
3 replies

Dec 20, 2012 1:30 AM in response to pkjok3r

Thanks Patrck,


However it now doesnt even want to turn on, as in I have swtiched it off, switched off the plug, left it off all night then this morning I turned it all back on again, the machine started up, the white screen with the applie logo came on with the wating circle symbol thingy.... then the screen goes blank, but machine is still running, then all the sudden the fan goes into hyper mode and is mega noisy and thats where is stays.


I have turened it off and back on again and it just goes straight to the blank screen and the fan kicks in....


this is very fistrating as I cant even get into the computer to see or change any settings.


This has all happened since I did the latest Lion OS update...


thanks,


Billy

Dec 20, 2012 11:15 AM in response to billyrollo

I would try doing an SMC and PRAm reset, if that doesn't work then see if it woll allow you to boot into recovery, once there verify disk permissions/repair disk permissions. If the problem presists from there re-install OS Lion (assuming you were able to get to the recovery partition.


SMC reset:

Shut off machine > Pull out the power cord from the back of the mac > While the cord is removed hold down the power button for 15 seconds > plug the cord back in and proceed to boot


PRAM reset:

Hold down Command + Option + P + R > trun on the computer and continue holding those keys down until you hear the startup chime 2-3 times


Recovery partition:

In order to boot to the recovery partition hold down the option key at startup, a screen should appear that has Mac HD and Recovery, go into recovery. From there select disk utility and this will allow you to perform first aid (I.E. repair disk, verify permissions, repair permissions)

If that does not work, again boot to recovery and select "reinstall Mac OS X"

My iMac 27" screen won't come on after sleep mode,

Welcome to Apple Support Community
A forum where Apple customers help each other with their products. Get started with your Apple ID.