iMac Restarts When It Should Sleep

Question

iMac Restarts When It Should Sleep

Late '15 iMac 21", Monterey 12.7.4 on external SSD, but keeping HDD updated as well.

There are always issues when an update comes along, major this time so I did a clean install on both drives. Set everything back up and all working well (even the HDD ran better).

I have always set screensaver after 20 minutes, sleep after an hour and require password after 4 hours. Now, whenever it is time to sleep, the machine restarts. I can set sleep to "Never" and I can set sleep (display off) to one hour if I do not "sleep" the drive with no issues.

There are many old discussions recommending Safe Mode, PRAM and SMC resets, reinstalls and closing processes running in Activity Monitor. The only one I have not completely done is closing processes because I have no way of knowing what they are doing or supposed to be doing-most make no sense to me.

I did an EtreCheck on the HDD and it came back with possible disk failure, kernal panics and malware (MalwareBytes found none). The SSD check indicated no major issues.

Other than this, the computer works amazingly well for an older machine/OSX.

any thoughts? Or should I keep the computer running with the display Off until it dies?

iMac 21.5″, macOS 12.7

Posted on Apr 29, 2024 12:06 PM

Reply

Answer 1

Allan Jones

Level 9

68,990 points

Apr 29, 2024 5:42 PM in response to Marc Schreiber

any thoughts?

Two.

—First, some external USB devices can cause sleep issues. Disconnect any (other the mouse and keyboard) and test. I wonder it the bootable external SSD is the culprit. Can you still boot the computer from the internal drive?

—Second, post the EtreCheck report. Most of the senior contributors here have reviewed thousands of such Something that seems innocuous to a new user can stand out as an issue to those of us with far more time with EtreCheck.

If you use the instructions in this User-submitted Tip, the EtreCheck report will not reveal any personal or security information:

How to use the Add Text Feature When Post… - Apple Community

Reply

Answer 2

May 1, 2024 2:32 PM in response to Marc Schreiber

Here is EtreCheck of SSD with all peripherals attached.

Note: With all peripherals disconnected, booted on HDD, the machine still restarted when going to sleep.

Also note, screensaver on or off, no difference.

HDD EtreCheck of External SSD

Reply

Answer 3

den.thed

Level 9

77,404 points

Apr 29, 2024 1:02 PM in response to Marc Schreiber

Disable the resource hungry Screensaver.

Turn on "Prevent automatic sleeping when display is off"

Leave the Mac ON and allow the display to turn OFF after 10 or 15 minutes.

Then shut down for longer periods of non-use and overnight if desired.

Reply

Answer 4

Old Toad

Level 10

207,751 points

May 1, 2024 3:28 PM in response to Marc Schreiber

You failed to include the report. Do it this way:

Copy the report

and use the Additional Text button to paste the report in your reply.

Then we can examine the report and see if we can determine the cause of the problem.

Reply

Answer 5

Old Toad

Level 10

207,751 points

May 1, 2024 4:01 PM in response to Marc Schreiber

You didn't copy it from within the app like the animated screenshot demonstrates:

Double click on the report on your desktop (or rerun it again if you've deleted it), click on the Share button and follow the screenshot.

Reply

Answer 6

hcsitas

Level 6

11,492 points

May 1, 2024 6:23 PM in response to Marc Schreiber

Sleep is unnecessary and should be disabled. Shut for long absences/idle overnights (i.e. do not manual-sleep), and for regular operation, use the settings exactly as shown below (display off-timer your choice), should fix.

Reply