27 iMac (2012) crashes and requires smc reset to turn on

HI all.

I have had the same problem for months. Today I have decided finally to leave my iMac in Genius Bar ( iMac 13,2 16 Gb Nvidia 680Mx, 128 Gb SSD, 1Tb HDD ). These are the tests carried out and the evidences I have collected:

Tests:

1) problem happens with fusion drive or without

2) with mountain lion, Maverick, Yosemite, El Capitan (Clean installation -> HDD & SSD formated)

3) with or without USB devices

4) with of without wifi

5) hardware test Ok

6) stress test Ok: CPU 4 cores 8 threads by terminal command and graphic card by specific Nvidia stress programme.

7) temperatures ok, below 95C under stress conditions

8) no kernel panic dumps

9) no grey screen during shutdown

10) SMC and NVRAM reset (SMC reset requires more that 5 min to go live)

11) SAT available.

12) Nothing repeatible at first look in the log file after every crash.

Evidences:

1) happens during OS X installation.

2) with only Safary

3) with gaming and photo edition programmes

4) running on a single programme or while changing from one to another.

5) time with no problems depends on unplugged time

I will be back when I have more information from Genius Bar.

kind regards,

Same problem. Three times to Apple Genius staff. Not fun shlepping this 27" iMac back and forth. Am on my third Apple Senior Adviser now.

I'll tell you what DOES work: boot in Safe Boot [Turn on power while holding down SHIFT]. Of course you lose a lot of video and audio. But it will work. Acts somewhat funky.

Now, why would I have to discover this myself? Why wouldn't Apple at some level suggest this as a workaround? Perhaps because it clearly narrows the problem. Why would Apple want customers to ask logically: Hey, it works in Safe Boot, but not normal boot? Can't you use that information to find a solution?

Too simple.

It's hard to imagine that Apple does not know about this issue.

I suspect that they will just stall all of us until the three year Apple Care Warranty expires, and that will be an end to it. Apparently they decided that it's better to waste the resources of Apple Genius Staff and Senior Advisers on this problem, than ship a replacement and honorable honor the Warranty. In business terms, the Apple Genius staff are fixed costs, as well as the Senior Advisers. So it costs Apple nothing to expend time on this useless pursuit.

On the other hand, to replace the iMacs DOES cost real money in terms of product shipped and not paid for. In addition, a cynical decision was made that a certain percentage of unhappy customers will purchase a new Apple machine, regardless of their experience.

And that's where we are. The Senior Advisers seem to be unaware of this thread, and there is a grand and laughable game of pretend: Apple pretends that they are honoring the Warranty, and you all pretend that you understand Apple's sincerity here.

These are defective computers, and all of us should start writing the Consumer Protection departments of your State's Attorney General office. Otherwise, you will just give up out of frustration.

One last thought, my warranty expires end of this month. I started complaining about this beginning in March. Although the Apple Senior Advisers assure me that they will still honor the warranty even after it expires, because I brought up the problem within the warranty period, does anyone really believe that as soon was the Warranty has expired, no one a Apple Care will even speak with you on the phone unless you start paying for service? You will be told that Apple Senior Advisers are not authorized to extend Warranties. After all a Warranty is a specific, written legal promise.

Well, I hope that helps this discussion. Remember: try Safe Boot for functionality, although limited. For some it may be OK.

I've had this issue from July till December. The first thing tried was a logic board replacement but it didn't do the trick. The second attempt was the power unite replacement. Outcome: not a single sudden shutdown for more than two months, and counting.

Robert how's things going with your machine after this replacement? After reading and watching this thread for some time I feel like we all need to come together and file something like mentioned before maybe with local Attn Gen or something this is a huge issue with so many people and nothing is being done about it.

I agree with you completely. I tried to post a link to a site with a call to action on it but Apple took it down. I understand they want to ignore the problem—but c'mon, anything with an Apple logo on it SHOULD be a symbol of quality, and as a faithful devotee of Apple (growing up we had Macs dating back to the Apple IIe) it really makes me second guess them if they fail to do the right thing now.

I am convinced that the error reporting system, the logs and files which Apple will request from you, the ACCS files, are worthless. Not only do they fail to point to the error, I have also found that the so-called Engineers do not come up with realistic solutions. So far, I have disabled a dozen programs, and half dozen plug-ins, disconnected my LaCie drive etc - - all based upon what the Engineers saw in the logs. None of those fixes worked. This is a case of throwing sh-t on the wall to see if it sticks. The logs, which you can see in the Console module, are simply unreliable. After all, wouldn't all this have been fixed long ago if the logs WERE accurate? The system logs are giving false readings.

When I brought my iMac to the Geniuses the first time, they reformatted my hard drive, and load fresh with Yosemite. Now, I am being advised by the third Senior Adviser I am dealing with to again bring it in to have the hard drive reformatted again. That tells me that they have no clue, and will not honor the Warranty. In effect, as many of you know by now, the Apple Care Warranty works like this: you get free Tech Support OVER the phone, after you come up with no solution from the Geniuses in the Apple Store. You will now act as a free Tech Support Assistant and perform all sorts of fixes on your iMac. There is no limit to the amount of time and inconvenience you will have to undergo, and there is no end point, at which Apple will replace your defective iMacs. You will spend hours browsing sites like this, trying to come up with technical explanations and so forth. Unlimited input from your part, and very limited and ineffective help from Apple. That's what your Apple Care Warranty really means.

In the real world, a billion dollar company would replace your purchase, and pretend at least to care about all the hours you have devoted to this and your frustration. Not at Apple.

For those of use old enough to remember, I recall similar frustration dealing with Windows 3.1 and the Files and Buffer settings. At that time Microsoft made an inferior O/S and we were all stuck with it. No apologies. That's how Apple captured market share in the end.

But now, the Apple strategy is to wear you out: make three trips to the Genius Bar, then out of frustration you will speak with a Senior Advisor. And after the Engineers throw cr-p on the wall with guesses, once again they will suggest that you bring it back to the Genius Bar where THIS TIME it will go to a special Apple Depot where they will REALLY get serious and fix these defective iMacs.

As I mentioned earlier, a workaround is to do a Safe Boot: power on while pressing SHIFT at the same time.

So they replaced with the same power unit, which will start to malfunction in two years?😀

Sjkmd your right for sure. I've worked in IT for awhile and this problem could be the worst one I've ever seen as you can't pin point what's actually causing it. I really feel for the people who need the computers for work related things like photographers, video editors, etc......I would have thrown this machine out the window months ago but like everyone here we try to remain patient but I'm loosing mine now. I was so reluctant to get this machine for this reason due to the fact it was self contained and if something needed work or troubleshooting hardware based it would be tough to get to and here we are. Brutal! My machine is not under AC any longer and after reading all these post I will not take it in until we find something credible to replace or fix. Might actually take mine and stand outside the Apple Store in Providence RI this coming weekend and demonstrate why not to purchase anything in the Imac series even if your like most people here and actually love the machine when it preforms right....I'll open PS and Lightroom and give it 5-10 minutes and let them see the screen go black without any real reason on a well maintained and immaculate machine 🙂 and say this will be you in 2 years.....anyone local want to join me?

Another one with same problem. 😟

Hope a upgraded power supply will be the fix.

Imac 27" Late 2012

Core i5 2.9

16 GB 1600MHz Ram

Nvidia Geforce GTX 660 512 VRam

Bought April 2013

First problems Dec 2015

Hey guys.

Sorry for my bed english.

Anyone has detected same problem using UPS? Sometimes the shutdown was generating by electronic component due to power supply problems.

Tomorrow I will go to take back my iMac 27 late 2012 from the Apple store here in Italy. It seems they have changed the power supply and the hard disk.

Let's see what will happen next weeks... but I am afraid that the problem will reappear...

This post has been seen more than 16000 times, how it is possible that Apple has not find jet a solution to this issue?

The computer has performed flawlessly since the power unit replacement. As I said before I could not get in touch with the guy that actually performed the replacement, otherwise I would have asked for specifics. All I can say is that I am quite sure that something was actually been done with the power unit, as the power button feels different now (a bit loose and sticking out a little bit).

Ciao.

Ho letto il tuo post.

Tu per caso usi un UPS? Vorrei capire se c'è qualcuno che ha rilevato gli stessi problemi anche utilizzando un gruppo di continuità.

Un saluto.

Hello, I don't use a ups unit.

Do you have the same issue with an ups?

**************

Ciao. no non uso un gruppo di continuità...

Tu hai lo stesso problema con un gruppo di continuità?

Hi all,

I have been reading the thread for a few month now and it is really staggering to realise we all are experiencing a very similar problem, on so many level, and yet, none of us has a good grasp on the issue nor can share a reliable solution, which is appalling since we all requested help from Apple via the Genius repair service.

Yes, you may have guessed, I am affected by the issue too, since August 2015. Though not directly, as this is my dad computer, who bought the iMac as a retirement treat early 2013. Still, I am really upset by his experience as it is a source of stress whenever he uses his iMac and worst as it impacts family well being.

I agree with many points raised here, and from what I gathered:

Product: iMac 27inch (late 2012)

Observed: Random Shutdown - switches from normal usage state to unpowered state, in an instant.

Frequency: every 10-30 minutes at worse, once a day at best.

After shutdown, iMac can be switched on by performing SMC reset only, with a duration unusually longer.

Noticed, the longer the computer is unplugged, the greater is the running time before next shutdown.

No software cause detected, regardless of the application running, it can happen

• on any supported OS X
• on a freshly installed OS X
• even while installing OS X

No hardware cause detected,

• no over heating
• Apple hardware analysis reports nothing
• Apple Store service found nothing

And it still happens after changing:

• motherboard
• power supply (some said so in the forum, but waiting on Robert response below)
• hard drive
• memory
• power cord
• connected devices

No predictive element or pattern found, ruled out:

user house electrical installation (since several iMac are running fine in the house, even using the very socket of the failing iMac, and this one still shutdowns when plugged anywhere in the house, with or without ups)

Hypothesis:

• The hardware not yet tested are the machine structure and the screen, and they correspond in date to the introduction of the brand new super flat screen design(which is now the norm).
• The frequency of shutdown and the SMC reset time influence seem to indicate a phenomena of charge, which, when reaching a limit, triggers the shutting down.

There is a sane suspicion to believe that those two observations could be linked, and that investigating them would provide a lead.

Question to Robert Van Dongen:

You have had the power supply component changed only and since then have seen once the issue, is it correct?

If so, anyone here that did the same but who still experienced the issue.

Question to Joe5000:

Do you have any update, statement from the Apple Representative? (yep, they deleted the contacts you provided)

Question to anyone:

Is any of you engaged in an higher discussion with Apple and have a reference on the ongoing process.

As per the Apple brand, this is not a local issue (France in my case), how can this issue be addressed in a global context?

Please keep providing any update you would come across.

Thanks,