iMac 27" 27" 2019, keeps restarting

[linkmaster6]

iMac 27" i5 3.1GHz A2115

Hi everyone,

So I've gotten my hands on a 2019 27" iMac that has had a history of randomly restarting due to some error. I've included the error report that popped up when I could get it restarted and have it remain going long enough to copy it over.

Originally this mac was running Ventura, there didn't seem to be any particular trigger causing the restarts but the frequency seems to bounce between every time it restarts to days in between. So far I have done the following and moved on to the next step due to the OS crash happening again:

-Reset NVRAM
-Ran bootable online system diagnostic, passed
-Ran repair install of MacOS Ventura
-Backed up data and erased the HD and reinstalled Catalina from the online recovery
-Attempted to upgrade to Ventura but kept running into an unexplained error
-Erased the drive and ran the Catalina install once again, upgraded to Ventura ok this time
-Ran the updates, installed them, also upgraded to Sonoma
-Ran a few 24 hour Youtube videos and seemed to be clear for a couple of days, but then fell into it restarting several time in the past 30 mins where it restarted over and over again.

Now regular PC I would normally roll into looking at swapping out RAM or the hard drive but given Apple's terrible decision to have adhesive be the only f'ing thing holding this together, I'm hoping that someone else has a better idea of what it might be. If there is a better log file I should upload let me know, I'm more of a Windows guy lol

 

[Raz0rEdge]

I'm confused by the panic happening in launchd. It's almost like some app starting caused the panic as opposed to a running application which would likely identify the app or the general kernel_task as the culprit.

Looks like you didn't spend much time in each version of the OS before jumping to the next, so hard to track anything there. Also, ensure that you don't install anything extra beyond the base OS to eliminate 3rd party apps.

You should also try to boot into Safe Mode and see if the machine stays stable there.

 

[ferrarr]

You should also try to boot into Safe Mode and see if the machine stays stable there.

I agree, this should be your next step. Start up your Mac in safe mode. The page I linked is for Sonoma, but it also goes back to High Sierra (macOS 10.13)

I don't understand, ram is easily replaceable in the iMac?

Have a look here to see what you are comfortable with,

iMac Intel 27" Retina 5K Display (Late 2014 & 2015) Repair Help: Learn How to Fix It Yourself.

Model A1419 / EMC 2806 / Late 2014 or Mid 2015. 3.3 or 3.5 GHz Core i5 or 4.0 GHz Core i7 (ID iMac15,1); EMC 2834 late 2015 / 3.3 or 3.5 GHz Core i5 or 4.0 GHz Core i7 (iMac17,1) All with Retina 5K displays

www.ifixit.com

 

[Randy B. Singer]

...there didn't seem to be any particular trigger causing the restarts but the frequency seems to bounce between every time it restarts to days in between. ..

In my experience Macs tend to spontaneously re-boot for one of three
reasons.

1) There is too much current draw on the electrical circuit your Mac
is attached to. For example, a refrigerator cycling on, or a laser
printer starting up, will cause a huge draw. It might be enough to
cause your Mac to have a hard crash and then re-boot.

2) Your Mac is overheating. With old Macs this might be due to the
accumulation of dust inside the case insulating the heat coming from
the motherboard. Or detritus in the case might be strangling your
fans. Or your fans may be failing. If it is one of the first two,
opening up your Mac and cleaning it out may be all that is necessary
to fix things.

3) A failing power supply (flyback) or simply cold solder joints
around your power supply. Often the heat cycling in your Mac expands
and contracts the solder joints and causes them to eventually crack
(you can feel these cracks with your fingernail - but don't try this
without discharging your power supply first!) and causes a
discontinuity. Touching the solder joints for the power supply with
the tip of a soldering pen to re-flow the solder easily fixes cold
solder joints.

I can't recall ever encountering a software problem that led to random restarts. I can see a software problem leading to an app constantly crashing, and maybe in an extreme case a kernel panic, but not random restarts.

I've seen a bad peripheral (or a bad connection cable) cause random crashes and restarts, but I haven't seen a case of that happening in years and years.

 

[linkmaster6]

Sorry for the MIA, had a busy few days on the road.
Forgot to recount in my history that when I wasn't getting an immediate reboot, before I would push any updates I would let the iMac run a 24 hour video on Youtube before moving on to updates or upgrades. Something to keep it busy and do a little work.
I've got it in safe mode now, it crashed the first time but allowed me to get logged in and get the 24 hour video running again this time so I will see how that goes.

Only items connected to the iMac right now is a USB mac keyboard and a mouse. Its currently hooked to an outlet where it is the only thing doing any major power draw. I can't say for certain what else was on the circuit at the original location though, but I don't think it was anything big. Originally it was in an upstairs office at an older man's home, only thing I could see near enough was an Acorn stairlift. But I can say for certain this wouldn't be a culprit as those have batteries under the seat for movement and the charger is low wattage.

I completely missed the door on the back, I'd recently taken another iMac apart and the RAM had to be accessed from behind the screen. I was just aiming to avoid doing that if I didn't have to.

Are there any other logs I should upload to give you guys a better picture on whats going on?

 

[ferrarr]

You can try EtreCheck

 

[linkmaster6]

You can try EtreCheck

I'll give that a check when I get back in front of it again.
Took a look at it this morning, it was still in Safe mode when I woke it up with the 24 hour video page still open (I'd turned off reopening apps). Told it to shut down (pretty certain) it oddly restarted and threw a crash report again, this time mentioning memory corruption. Popped one of the two sticks out and have it running the video again out of safe mode.

 

[techiesteve]

Or your fans may be failing. If it is one of the first two,
opening up your Mac and cleaning it out may be all that is necessary
to fix things.

For anyone intending to clean out dust and fluff, there is only one fan. Don't just clean it from the front. Loosen the 3 screws holding it in and disconnect its connecter from the logic board, then remove the fan. Clean the fan blades on the reverse side, that can't be done with the fan it situ. The bottom vents can also become partially clogged too, some of these series of iMacs when transported for service can have dangling fluff hanging from the bottom vents, not a good sign. Most of the iMacs I see that are clogged with dust and fluff are the earlier 2012 models.

 

[linkmaster6]

Ok so 100 hour video down on a single stick of ram, no crashes or restarts. I've shut down, put the removed stick back in and removed the other stick and I'm running some videos again.

 

[linkmaster6]

Sorry for the MIA, got busy with other things.
Isolated the mac a bit more, its on a circuit where it is the only thing drawing power. Seemed to be good for the last week but it looks like it has restarted on me over night.
Here is the last error report as well as the report from Etrecheck, the unsigned item on the Etrecheck report is Amazon photo

 

[Jaqm]

I was living the same nightmare like you, I just opted to install a Windows 11 on an external SSD and move on with my life.
The fact that Windows works fine makes me think that the problem might be on the internal (and really hard to disassemble) SSD. While on windows I can't see the mac drives and everything works like a charm. That's why I thought about the Drive. I Also tried to run a macOs on an external drive but it kept rebooting.

 

[Randy B. Singer]

I Also tried to run a macOs on an external drive but it kept rebooting.

That would indicate to me that the problem has nothing to do with your internal hard drive, but rather has something to do with how you have the Mac OS set up.