iMac operating suspiciously

[GallenH]

iMac 27" c.2014 10.13.06. This just started: I put computer to sleep at night (as I always have). Come back in the morning and the computer is shut down. Or so I thought. Push button to boot up and nothing happens. Disconnect power cord for about a minute and plug back in. Computer starts up. This isn't a one-time happening. It has happened consistently night after night for about 4 days.

Please advise.

thx.glenn

 

[Fishrrman]

I'll offer a suggestion.
This IS NOT "a fix" or a solution.
Just something to try.

For the next 2 or 3 nights...
Instead of "sleeping" the iMac, SHUT IT DOWN -- power off.
If you do this, will it start right back up again next morning...?

 

[velocityg4]

Unplug external devices. Except your keyboard and mouse. Then try the nightly sleep. To see if it is some problem with external devices causing sleep issues.

 

[Willo34]

Agreed with the suggestions above. This sounds like it could be a logic board problem related to the sleep sensor.