Q: Why is my imac shutting down by itself?

Since I installed the Macs Fan Control 1.3.0, that advised by the user maX2.lover last week,

hopelessly today, my iMac shut down itself again in twice!!!

I can't say the app couldn't help, but I'm confusing what's happening...

and reading the posts before,

someone said hard drive's problem, someone said...

and I'm wondering if high humidity will cause that problem...

Oh... that's made me confusing

I had no idea to solve it, HELP!!!

I installed the fan controller too. I've passed from hourly shutdowns to shutting down every 4-5 hours.

So it seems it has some effect though it is not near definitive.

I use iStat Menus (though Macs Fan Control is said to be pretty good). However, if you're still having problems with shutdowns due to excess heat, you might want to increase the fan significantly.

I keep my fan at 2000 rpm all the time - or go even higher if I've editing video or gaming.

Oh I see...it might be my fan was keeping in low speed, I kept it at 1200rpm instead all time.

Yeah... I've editing and convert video or gaming or photoshop too.

I'm still wondering if high humidity will cause that problem...

Because here is hot and humid... it's about 35℃ and 95%.

So, I'm trying to keep it at 2500rpm, really hope the problem can be solved.

Let's try and thanks for your advice, poikkeus1.

Bella Joey wrote:

 

Oh I see...it might be my fan was keeping in low speed, I kept it at 1200rpm instead all time.

Yeah... I've editing and convert video or gaming or photoshop too.

I'm still wondering if high humidity will cause that problem...

Because here is hot and humid... it's about 35℃ and 95%.

So, I'm trying to keep it at 2500rpm, really hope the problem can be solved.

Let's try and thanks for your advice, poikkeus1.

Actually, you have a very good point. "Hot and humid" might make a machine hotter than one in a dry climate. Sadly, the only solution I can come up with is painfully obvious: pump up the fans on your computer. In your case, 2500rpm fans just might do the trick.

In fairness, this entire thread is actually a combination of potential problems:

1. Power supply. That's a really frustrating problem, but it's relatively easy to diagnose. The best solution is preventative: keep temperatures low.

2. Overheating computer. Depending on the model or how you configure your machine, high temperatures are going to be less damaging if you keep the fans blowing.

3. Logic/graphics board problem. Certain vintages of machines (like the early 2011 MacBook Pro) are more prone to this issue, presumably because of a faulty graphics board. But high temperature computing can make this issue worse.

In every case, these problems can be treated by aggressively reducing temperatures/increasing fans.

iMac (27-inch, Late 2012)

Processor 3.4 GHz Intel Core i7

Memory 32 GB (16GB Apple, 16GB Crucial: Both Brand New)

Graphics NVIDIA GeForce GTX 680MX 2048 MB

OSX Yosemite: Version 10.10.3

Okay, my iMac keeps shutting down and here is what has been done so far:

New power supply module

New Display Screen

New Logic Board

Disk Wipe (Restored to only the software that came with the system)

Verification of the Disk with Disk Utility and Repair of Permissions

Removal of all external devices

Apple sent me new RAM (16GB to replace the ones I have)

Crucial sent me new RAM (16GB to replace theirs)

I have performed so many SMC resets that I have lost count.

The apple care specialist has taken the logs from my computer and suggested that it was a software issue. (so as mentioned above I wiped the disk and reinstalled OS X: I did not restore anything from my backups; still randomly shuts down)

I'm working with my second Apple Care Specialist, and my second Apple Care repair service company. Can anyone help me figure this out? I'm on the phone with Apple Care right now.

General Response in relation to all things concerned:

How about a Dyson Humidifier to help with Humidity BellaJoey? or using the computer in the coolest and driest part of the house/unit… think this would be the best solution…

Before installing the fan control unit, I had the hard drive die stating S.M.A.R.T issues causing death and the Yosemite that was installed over Mavericks Partition died (machine was revving loudly and getting extremely hot) However that internal hard drive has been externalled and are not having any issues with it, other than it appears to think that whilst it is external that it is still in the machine… (turns itself on and off as it pleases).

Only the Mavericks Partition survived before being cloned and a fresh (clean) install of Yosemite on a New hard drive (original equivalent running to the same specs) but taking up a lot less space in the same position that the original sat, leaving a gap (air can get in) and not touching the external casing (for which from observation keeps a lot of heat in and against the hard drive) So from observation could become problematic.

Since this time (Hard drive upgrade) the Computer no longer PRAM boots or SMC resets in Yosemite (or runs diagnostics when booted in that mode) but am running Mavericks on a separate partition and the hard drive switches to it any time I need to do this.

Have also attempted re-installing the EFI Firmware update (iMac EFI Firmware Update 1.9 Feb 23, 2012) but it doesn't recognise this either as it needs to be installed in an earlier version of the Operating System (or so it says) So am under the assumption that an EFI Firmware update is needed also.

In the process of all this happening, I read that the particular model purchased was known to have faulty hard drives (for which I didn't realise until a newer one was installed and the machines transfer speed appeared to double, but this could be seen as an assumption if the hard drive is taking in heat from the casing) and that the Graphics card was also known to be faulty. Since the new hard drive has gone in my computer is not showing the same glitchy (pixelated screen) type of behaviour (as much) at start up or when running from externalled System Software.

I hope that this helps and that everyone gets their issues sorted soon (or that Apple comes to the party), it's a bit of a tragedy with newer machines behaving badly; One would expect the life span/expectancy of them to be a bit longer than having to replace them every 2 or so years, it's not sustainable nor is it a wise use of the worlds resources.

I am having the same the problem. Before taking in the computer to an apple repair service I was wondering: why is it that when I run the machine in safe mode, it never crashes?

Also, I looked up on the console log, and there, its stated that the shutdown cause was "0" which appears to be related with the power cord being pulled off/loss of energy supply. But, as I said, the power supply doesn't fail when in safe mode. Any thoughts?

same problem here with a recently bought (2nd hand) 27 inch 2TB, 16 Gb ram imac

try to figure out what the cause is of the sudden shutdown by taking a look at the console diagnostics but it's not clear to me;

this is part of the diagnostics (it's even taling about a suspect file?!?!):

i have read all the posts in this discussion and to me it's clear that the cause is not clearly one issue/culprit; overheating keeps coming back in the discussion so yesterday i installed Mac Fan Control which is now humming at a 1900 RPM for the cpu...

Process:         mdworker32 [741]

Path:            /System/Library/Frameworks/CoreServices.framework/Versions/A/Frameworks/Metadat a.framework/Versions/A/Support/mdworker32

Identifier:      mdworker32

Version:         800.29

Code Type:       X86 (Native)

Parent Process:  launchd [278]

Responsible:     mdworker32 [741]

User ID:         502

Date/Time:       2015-06-16 16:17:15.958 +0200

OS Version:      Mac OS X 10.9.5 (13F1077)

Report Version:  11

Anonymous UUID:  62496410-AFDA-E872-6A06-62B1B23384AB

Crashed Thread:  4

Exception Type:  EXC_BAD_ACCESS (SIGSEGV)

Exception Codes: KERN_INVALID_ADDRESS at 0x000000000880c020

VM Regions Near 0x880c020:

    mapped file            000000000878e000-00000000087e4000 [  344K] r--/r-x SM=PRV  /Users/USER/Documents/*/*.qxd

-->

    mapped file            000000000883b000-0000000008ca8000 [ 4532K] rw-/rwx SM=COW  /private/var/folders/*/*.csstore

Application Specific Information:

import fstype:hfs fsflag:480D000 flags:40000007E diag:0 isXCode:0 uti:com.quark.xpress.doc plugin:/Library/Spotlight/QuarkXPress.mdimporter - find suspect file using: sudo mdutil -t 1517026

Application Specific Signatures:

import uti:com.quark.xpress.doc plugin:/Library/Spotlight/QuarkXPress.mdimporter uuid:BCF14709-BA7D-4B2E-84AD-2B1EBDC71A46 2.0

Thread 0:: Dispatch queue: com.apple.main-thread

0   libsystem_kernel.dylib         0x02d30f7a mach_msg_trap + 10

1   libsystem_kernel.dylib         0x02d3016c mach_msg + 68

2   com.apple.CoreFoundation       0x00ea8bf9 __CFRunLoopServiceMachPort + 169

3   com.apple.CoreFoundation       0x00ea81d1 __CFRunLoopRun + 1393

4   com.apple.CoreFoundation       0x00ea79ea CFRunLoopRunSpecific + 394

5   com.apple.CoreFoundation       0x00f6a221 CFRunLoopRun + 129

6   mdworker32                     0x0005282f 0x48000 + 43055

7   libdyld.dylib                 0x02ba4701 start + 1

Thread 1:: Dispatch queue: com.apple.libdispatch-manager

0   libsystem_kernel.dylib         0x02d36992 kevent64 + 10

1   libdispatch.dylib             0x02b77899 _dispatch_mgr_invoke + 238

2   libdispatch.dylib             0x02b77532 _dispatch_mgr_thread + 52

Thread 2:

0   libsystem_kernel.dylib         0x02d36046 __workq_kernreturn + 10

1   libsystem_pthread.dylib       0x02e2edcf _pthread_wqthread + 372

2   libsystem_pthread.dylib       0x02e32cce start_wqthread + 30

Thread 3:

0   libsystem_kernel.dylib         0x02d36046 __workq_kernreturn + 10

1   libsystem_pthread.dylib       0x02e2edcf _pthread_wqthread + 372

2   libsystem_pthread.dylib       0x02e32cce start_wqthread + 30

Thread 4 Crashed:

0   com.apple.LaunchServices       0x037c1988 CSStoreGetGeneration + 9

1   com.apple.LaunchServices       0x037c659f _LSDatabaseNeedsUpdate(LSDatabase*) + 53

2   com.apple.LaunchServices       0x037c0398 _LSContextInit + 128

3   com.apple.LaunchServices       0x037d071c _LSCopyInfoForNode + 134

4   com.apple.LaunchServices       0x037d2819 _LSCopyItemInfoForRefInfo + 131

5   com.apple.LaunchServices       0x037d26ee prepareBasicFlags(__CFURL const*, __FileCache*, __CFError**) + 162

6   com.apple.LaunchServices       0x037bfc6d LSPropertyProviderPrepareValues(__CFURL const*, __FileCache*, __CFString const* const*, void const**, long, void const*, __CFError**) + 47

7   com.apple.CoreServicesInternal 0x082e8498 prepareValuesForBitmap(__CFURL const*, __FileCache*, _FilePropertyBitmap*, __CFError**) + 291

8   com.apple.CoreServicesInternal 0x082e651e _FSURLCopyResourcePropertiesForKeysInternal(__CFURL const*, __CFArray const*, void*, __CFError**, unsigned char) + 899

9   com.apple.CoreServicesInternal 0x082e6196 _FSURLCopyResourcePropertiesForKeys + 38

10  com.apple.CoreFoundation       0x00eb917c CFURLCopyResourcePropertiesForKeys + 108

11  com.apple.desktopservices     0x0098eff8 TCFURLInfo::FetchProperties(bool) + 90

12  com.apple.desktopservices     0x0098ef3f TCFURLInfo::Initialize(__CFURL const*, bool, bool) + 145

13  com.apple.desktopservices     0x00a0d5bf _CopyPropertyStoreWithURL + 104

14  mdworker32                     0x00058394 0x48000 + 66452

15  mdworker32                     0x00054f49 0x48000 + 53065

16  libsystem_pthread.dylib       0x02e2d5fb _pthread_body + 144

17  libsystem_pthread.dylib       0x02e2d485 _pthread_start + 130

18  libsystem_pthread.dylib       0x02e32cf2 thread_start + 34

Thread 4 crashed with X86 Thread State (32-bit):

  eax: 0x0880c000  ebx: 0xb0193f00  ecx: 0x01174000  edx: 0xb0193920

  edi: 0x037c0329  esi: 0x0000089f  ebp: 0xb0193908  esp: 0xb0193908

   ss: 0x00000023  efl: 0x00010246  eip: 0x037c1988   cs: 0x0000001b

   ds: 0x00000023   es: 0x00000023   fs: 0x00000023   gs: 0x0000000f

  cr2: 0x0880c020

Logical CPU:     2

Error Code:      0x00000004

Trap Number:     14

i'm pretty sure that this shutting down is not a 'overheated' issue,

my imac is rather cool and the temperature does not go higher than 33 degrees celsius, less than body temperature :-)

i found another suggestion: run disk first aid and reinstall the os

that's what i'm gonna try right now

btw: my imac shut itself down today after having been on for a number of hours, it happened while i was away from my desk, so the imac wasn't really busy at the time; in the energy saver i had set the energy saver to Never for the computer and 20 minutes for the screen; mac fan was working

Same problem here also. Mine is late 2012 Core i7 with 16GB RAM. It is now around 18 months old. For the first one year it was sparingly used. Began to use it as a full time system only in January this year. The system began to show similar symptoms discussed here. In the beginning it shuts down itself only 2 or 3 times a day, but now it shuts down itself more frequently, say even after 15 minutes of use. Originally it was ML (10.8.3) pre installed and part of the troubleshooting I upgraded to Mavericks 10.9.4 but no luck. It continued to behave similar to before even after OS update. Again to isolate trouble I dismantled the fusion drive and installed Mavericks in the Intel SSD drive (in built). Nothing better, it continued to shut down itself and the system is now almost unusable. I can get it to work 2 hours maximum before it shuts down. The more time I unplug it from the power outlet the more it will stay on. If I restart it again with in 15 minutes after a shutdown, it will shut again down in the next 15 minutes.  No matter, you power up and put it to sleep for a while, the system will shut itself down with in minutes after you wake it up. This is not overheating issue. The system is using under AC and the temperatures are normal. I have tried IState Pro and Fan controls to over crank the fans with no luck. My warranty is over and no Apple care. I am frustrated. It is not easily serviceable and replacing parts such as logic board or even power supply is highly expensive and time consuming in India. Almost wasted my hard earned $3000 in a faulty Apple Computer.

Rajiv

i agree, overheating is not the problem, i am using istat and the temperature shows a moderate 30-32 degrees celsius, nothing to worry about;

mine is shutting down less often, sometimes once a day, sometimes once in a few days, i only got his mac a week ago so i am not sure if it is getting worse;

you mention replacing the logic board etc. but beware, i have read all the posts on this issue and even replacing the logic board or power supply is no a guarantee to to solve the problem, that's the most frustating: nobody knows what's happening and how to solve it!

I found a fix for my machine. Although I reckon the problem should be the power supply, now, when I shut down the iMac, I also unplug it from the power outlet socket. By doing this, I've gone from constant shutdowns in a day, to zero shut downs in almost two weeks. Every time I want to use it, I plug it in. Every time I'm done using it, I take it off from the socket. For some reason, this fix is working for me. Granted, a machine this expensive should be able to be connected 24/7 without issues, but perhaps some faulty power supplies are at the origin of the problem, depending on your house's power circuit...

amazing! i am gonna try it, of course but it sounds too crazy to be true!

my imac power plug sits in a 'multiple socket' with a red switch to turn it off when none of the plugs is in use;

how could a shut down imac be influenced by a power plug??

anyway, i am gonna give it a try!

one more thing that strikes me: almost all the times it happened (shutting down) i was away from my desk, so the imac was not in use;

energy saver for the computer set to Never, energy saver for the screen set to 15 minutes;

seems like the imac is more vulnerable when it is not in use (just guessing)

still searching other forums for this problem; one thing that keeps coming back: dust

people reported to have solved the problem by cleaning their mac; they had macs that could be opened, i would not know how to open my 27 inch imac!

btw: this problem also occurs with pretty new imacs, it does not make a lot of sense that these macs are suffering from a lot of dust, does it?

I also have one similar to those. Give it a try. Shut down the iMac, switch the socket off (use the switch on the expansion if you want), and leave it like that, overnight for example. Then, continue to it like I've said. Sounds strange, but I was ready to take my iMac to the Apple Store, when I gave this a try and it seems to be working. Not a single crash since.