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

Hard Drive??

hm... after your imac shuts down... can you turn up again or do you need to wait some minutes to power up again?

The imac must be disconnected for at the very least 30 seconds or the power button will fail to turn it back on.

30 seconds is too fast to recover the imac, maybe they're right with the HDD check..

Clearly I am not experiencing the same issue that others in this thread are with their Imac.

Regardless of your expert opinion I will still be reporting how things turn out.

When my iMac had the shutdowns I had to unplug the power for about 1 Minute before I could do the restart.

Finally i have received my PSU LiteOn, I'll replace it tomorrow, i hope it works because there are some sign of use..

Will keep in touch with thread..

3 days working with it... no shutdowns... i´ll keep alive this thread with my updates for 1 week...

but everything aims that was a PSU problem 🙂

Thanks for your update, great to know that it has solved your issue as well (as it seems now)

Hi guys,

I have changed the Liteon PSU for 6 months. It is working fine. I have keep my computer for entire month. No problem at all.

Good to read, another point for PSU.

I join this club with my late 2012 iMac 27inch. My iMac also won't starts up anymore. This screen appears. Bjorn78 did you solved this problem?

Hi all

Just an update, 6 months after replacing my PSU I have not experienced any random shutdowns.

And I am not even shutting down my iMac anymore, just put it into sleep mode.

I also have this problem.

Is there anyone who has installed a LiteOn power supply who is still experiencing this issue?

Thanks for posting your experiences. Please let us know if the problem reoccurs.

FWIW, in the US at least, Apple has been replacing the faulty hinge free of charge.

Just for info here. I just replaced my power supply with a LiteOn. Too early to say, but no issues yet. Before, it was shutting down every day..