Unusual iMac crashes happening several times a day

Question

Level 1

39 points

Unusual iMac crashes happening several times a day

Hi,

I have a 2013 iMac, intel i7 quad core 3.4GHz, 16 gb RAM, 3TB Fusion drive that keeps on crashing.

It's an absolute nightmare as invariably it crashes whilst I am doing work.

Generally, I work on graphic design but also music. Rarely are more than 5 apps ever open at once. I don't play games, watch videos, etc. It's purely used for work.

What's odd about these crashes (based purely on my experience of occasional mac crashes since having a G4 Powerbook and Macbook 15 years ago through various MacBook Pros and now to this iMac) is that although the screen goes completely black (and mouse/keyboard completely unresponsive) the Power button has no effect. I can tap it or hold it down for a few seconds (or longer). Nothing. This seems very unusual to me. Normally crashes just mean the computer closes down and using the power button restarts it. But here it doesn't. I have to go under the desk, unplug the iMac, wait a while and plug it back in. Only then will it restart and make the startup sound.

Very often, as soon as the grey screen with Apple logo and loading indicator passes and the log in screen appears, it crashes again at this point.

I was fortunate (or unfortunate one could say) to catch this on video the other night as it seemed to happen 5 or 6 times in a row. I can upload this video

OK, that's the issue.

Now, some background as I know I'll inevitably be asked. The IMac started doing this in December, rarely at first, then increasing in frequency. I decided to back it up and wipe it and migrate only the absolute minimum of apps, system preferences, app support etc etc manually (rather than migration assistant, in an attempt to minimise likelihood of me bringing what was causing the problem back over). It didn't work. The crashes resumed. I was also on Live Chat and phone call to Apple on two occasions and they were not able to help. I was unable to start the mac in Safe Mode as that was needed. It crashed every time this was tried just at the point it reached 97% completion. They assumed some disk corruption or partition problems. I also took it to a local iRepair for them to look at but it never repeated the crashes so they couldn't identify the problem, annoyingly. It was fine for them! And funnily enough since bringing it back it also worked here. I had no idea why. But then two weeks ago it started happening again....and now it's happening several times a day....I've lost design work, bits of music projects and so on. It's unbearable.

I've embedded a link to what I managed to video...apologies for it being over 2 mins....it was a tedious process and all the harder with one hand! :)

Any insight much appreciated.

Thanks

Gordon

iMac Line (2012 and Later)

Posted on Mar 18, 2020 9:43 AM

Reply

Answer 1

Top-ranking reply

Kappy

Level 10

361,855 points

Mar 18, 2020 10:41 AM in response to gkmach1ne

No embedded link, btw.

A Troubleshooting Procedure that may Fix Problems with macOS El Capitan or Later

You should try each, one at a time, then test to see if the problem is fixed before going on to the next.

Be sure to backup your files before proceeding if possible.

Shutdown the computer, wait 30 seconds, restart the computer.
Disconnect all third-party peripherals.
Resetting your Mac's PRAM and NVRAM
Reset the System Management Controller (SMC)
Reset your Startup Disk and Sound preferences, if needed, after resetting the PRAM.
Test in safe mode to see if the problem persists, then restart normally. Use safe mode to isolate issues with your Mac and Playing Safe - what does Safe mode do?
Repair the disk by booting from the Recovery HD. Immediately after the chime hold down the Command and R keys until the Utility Menu appears. Choose Disk Utility and click on the Continue button. Select the indented (usually, Macintosh HD) volume entry from the side list. Click on the First Aid button in the toolbar. Wait for the Done button to appear. Quit Disk Utility and return to the Utility Menu. Restart the computer from the Apple Menu.
Repair permissions on the Home folder: Resolve issues caused by changing the permissions of items in your home folder.
Create a New User Account Open Users & Groups preferences. Click on the lock icon and enter your Admin password when prompted. On the left under Current User click on the Add [+] button under Login Options. Setup a new Admin user account. Upon completion log out of your current account then log into the new account. If your problems cease, then consider switching to the new account and transferring your files to it - Transferring files from one User Account to another.
Reinstall OS X by booting from the Recovery HD using the Command and R keys. When the Utility Menu appears select Install OS X then click on the Continue button.
Erase and Install OS X Restart the computer. Immediately after the chime hold down the Command and R keys until the Apple logo appears. When the Utility Menu appears:

1. Select Disk Utility from the Utility Menu and click on the Continue button.

2. When Disk Utility loads select the drive (out-dented entry) from the Device list.

3. Click on the Erase button in Disk Utility's toolbar. A panel will drop down.

4. Set the Format type to APFS (for SSDs only) or Mac OS Extended (Journaled.)

5. Click on the Apply button, then wait for the Done button to activate and click on it.

6. Quit Disk Utility and return to the Utility Menu.

7. Select Install OS X and click on the Continue button.

Reply

Answer 2

gkmach1ne Author

Level 1

39 points

Apr 3, 2020 2:03 PM in response to Kappy

Well, I didn't think I'd be back here so quickly, I must admit.

But the iMac crashed when logged into the new admin account that I created.

Which means the only things I've not done in your suggested list of things to do are:

Reinstall OS X by booting from the Recovery HD using the Command and R keys. When the Utility Menu appears select Install OS X then click on the Continue button.
Erase and Install OS X Restart the computer. Immediately after the chime hold down the Command and R keys until the Apple logo appears. When the Utility Menu appears:

1. Select Disk Utility from the Utility Menu and click on the Continue button.

2. When Disk Utility loads select the drive (out-dented entry) from the Device list.

3. Click on the Erase button in Disk Utility's toolbar. A panel will drop down.

4. Set the Format type to APFS (for SSDs only) or Mac OS Extended (Journaled.)

5. Click on the Apply button, then wait for the Done button to activate and click on it.

6. Quit Disk Utility and return to the Utility Menu.

7. Select Install OS X and click on the Continue button.

BUT, I did do something like this at the end of January. I completely wiped the disk and installed a completely new OSX (the iMac was on High Sierra...and I went straight to Catalina). After this I had a completely clean mac with nothing on it. I was reluctant to use Migration Assistant to get all my files and applications back on as I wasn't sure what the problem was. I wondered if something was corrupted. So decided to manually move a few things over from the external hard drive onto which I'd backed up. I decided to only move a few crucial apps and settings....everything else I installed from scratch which was a major hassle. To this day, the iMac never did resume its former splendour as I never did drag everything back over....as you can tell by this thread...it started crashing again.

Something worth pointing out is that the backups looks differently arranged to those of my MacBook (and previous Macs) . Instead of just seeing Macintosh HD, I now see f our folders: Macintosh HD, Macintosh HD - Data, Macintosh HD 1 and Recovery. Is this a Catalina thing? Both the second and third folder have Applications, Library, System, Users folders in them.

Prior to the end of January when I last did a 'proper' back up that had all my stuff on it (8 January) the hierarchy also looked weird, for example I had two almost identical user names in Users, one of which had only the Library in it, the other had everything other than the Library in it. That always perplexed me. I never consciously did that. I suspect one of them is from migrating aspects of a back up from a previous laptop over when i first got the iMac.

What a mystery....anyway, it's now off and not switching on

Sorry if you've had to read all this! :)

Reply

Answer 3

gkmach1ne Author

Level 1

39 points

Apr 27, 2020 1:16 PM in response to gkmach1ne

Any further thoughts on this anyone?

I recently managed to switch the iMac on....and it's been on for about 6 days solid now in a different corner of the studio without a crash....BUT I've not connected it to my Presonus StudioLive 16.0.2 in case it's that that's causing it.

Also, what it IS doing is that loud rattling, drilling noise, from the back where the fan is. Is there somewhere I can upload this video without having to upload to Youtube for the world to see?

Could the fan be the problem?

I happened to also be going through old Apple emails and found this one which I'd forgotten about (screenshot attached. Could this be related to the crashes??

Reply

Answer 4

gkmach1ne Author

Level 1

39 points

Mar 20, 2020 4:17 AM in response to Kappy

Hi Kappy,

One more thing, that might be important....the computer has also started making a whirring noise (actually for a while I thought it was someone drilling outside some distance away until I realised it was coming from inside the machine) that seems to ebb and flow in 20 second cycles getting louder then quieter, sometimes even speeding up and getting higher pitched. I'll try and upload videos.

In terms of your suggested procedures, I have't started on these yet but will go straight into the ones I've not tried, starting at 3 because within the last moth I've already tried 1, 2, 6 (and the machine can't do this), 9, 10 and 11.

Thanks,

Gordon

Reply

Answer 5

Kappy

Level 10

361,855 points

Mar 20, 2020 10:51 AM in response to gkmach1ne

I can only guess on this one. There are only a couple of internals that are spinning: HDD and fans. Now, of the steps in my procedure that you have done, I need to know if you were able to try Safe Mode. If you are able to boot into safe mode, then the crash isn't likely caused by hardware failure. If there was no problem with safe mode, then while you are in safe mode open Users & Groups preferences and create a new Admin user account. Restart the computer and log into the new user account, not your usual one. Does the computer still crash?

Reply

Answer 6

gkmach1ne Author

Level 1

39 points

Apr 3, 2020 6:20 AM in response to Kappy

Hi Kappy,

Sorry for such a slow response.

I've barely been able to get the iMac to stay on lately so using another computer. Annoyingly all the repair shops are closed at the moment due to the lockdown so I can't even take it away to get looked at.

To answer your question, yes, I was able to start the iMac in Safe mode and it didn't crash. This was new because before, even while I was on the phone to Apple, it was crashing right in the middle of opening in Safe Mode....well, around 95% completion according to the loading bar, which got stuck at 95% for a good couple of minutes before finally the screen going black.

This time it did work and I was even able to back it up whilst in Safe Mode.

I have only just created another admin account today and have just logged in. I will report back.

Thanks for your help and patience.

Best wishes

Gordon

Reply