Imac won't sleep af 2016-004 update

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Level 1

8 points

Imac won't sleep af 2016-004 update

After I yesterday applied security patch 2016-004 to my Imac ( dec 2010 model) I can't enter sleep mode. I have tried to make a safe boot ( Found a note on the net, that it fixed the problem for some) but it doesn't for me

When I try to use sleep mode - the screen goes blank as normal and my external USB disk spins off - but i sounds like the fan in the Imac does not spin down. After a few minutes it switches on the screen again

Until yesterday everything worked fine - and the security update is the only change I have made

Any ideas ?

Carsten Fuhr

Denmark

iMac, OS X Yosemite (10.10.5)

Posted on Jul 29, 2016 3:14 AM

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Answer 1

SeaPapp

Level 7

26,492 points

Jul 29, 2016 3:18 AM in response to cfuhr

Try resetting the SMC Reset the System Management Controller (SMC) on your Mac - Apple Support

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Answer 2

cfuhr Author

Level 1

8 points

Jul 30, 2016 2:27 PM in response to SeaPapp

Sorry for the late answer - I did not make any difference with a reset of the SMC. It's still the same - it seems to sleep around a minute, and then the screen comes on again. Have check the activity monitor - no programs are preventing sleep mode. Out of ideas !

Carsten

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Answer 3

SeaPapp

Level 7

26,492 points

Jul 30, 2016 4:13 PM in response to cfuhr

Take a look at your settings.

From the Apple menu, choose System Preferences.
From the View menu, choose Energy Saver.
Make sure "Wake for network access" isn't checked.
OS X Yosemite: If your Mac won’t go to or stay in sleep
If your Mac doesn't sleep or wake when expected - Apple Support

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Answer 4

cfuhr Author

Level 1

8 points

Jul 31, 2016 12:39 AM in response to SeaPapp

Hi

I have tried all the basics like energy settings etc - And nothing has been changed except for applying the security update

Carsten

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Answer 5

cfuhr Author

Level 1

8 points

Aug 1, 2016 12:18 AM in response to cfuhr

The problem is now solved - it seems that it was caused by a USB harddisk... now it sleeps like a baby

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Answer 6

SeaPapp

Level 7

26,492 points

Aug 1, 2016 2:55 AM in response to cfuhr

As suggested in both support articles I linked to. Gald you found your problem.

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Answer 7

cfuhr Author

Level 1

8 points

Aug 1, 2016 12:40 PM in response to SeaPapp

Back to scratch... i won't go to sleep again. Not even with the usb disks pushed out, and the disks switch off. so i must be something else, that brings it out of sleep after a minute. Still strange, because nothing was changed except the security patch - any ideas ?

Carsten

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