2013 iMac

[seabreeze56]

I just got my husband a "new" late 2013 iMac desktop as his old one couldn't be upgraded anymore and became useless. So... they forgot to send the power cord so I just used the old one. It worked but..... when putting it to sleep, it shuts down instead of just going to sleep. I googled this issue and I come up with "bad power cord." Could this be the only issue?? I called the place I bought it from (it has a 90 day warranty) and asked them to send me the power cord. Which they are doing and were apologetic. I told them the problem of the computer shutting down instead of sleeping. They said it was because of the cord. Is this true?? Will this fix this issue?

 

[Juicy Box]

I never heard of the power cord being the issue, and am not really sure what the cord has to do with anything, but I have heard of plenty of sleep related issues.

I would start with resetting the SMC:

Reset the SMC of your Mac - Apple Support

The SMC is responsible for managing power on your Mac. Resetting it can resolve certain uncommon issues related to power or thermal management.

support.apple.com

Simple instructions:

1. Choose Apple menu > Shut Down and wait for your Mac to shut down.
2. Unplug the power cord.
3. Wait 15 seconds.
4. Plug the power cord back in.
5. Wait 5 seconds, then press the power button again to turn on your Mac.

If this doesn't work, maybe try booting in safe mode and see if the issue is still there, or maybe resetting the NVRAM/PRAM.

Here is resetting the NVRAM/PRAM:

Reset NVRAM on your Mac - Apple Support

If one or more settings stored in NVRAM don't work as expected on an Intel-based Mac, resetting NVRAM might help.

support.apple.com

Also simple instructions, shut down your Mac, press the power button to start it up, and right after the start up chime, hold the following keys on the keyboard:

Option Command P R

You can release the keys after you hear the second start up chime.

I am unsure if resetting the NVRAM/PRAM would correct sleep issues though, but it is super easy and quick to do, might as well try.

Let us know what happens.

 

[seabreeze56]

I really didn't think it could be the power cord either but.... when I plugged it in with the old cord from the old computer, there was no DING sound. I DID find the power cord to this new computer - they had it packed DEEP in the packing material. So.... I plugged it in with it and started it up and there was the DING start up like it should do. So..... I don't know - it could be. There are a lot of google answers that say if it does shut down rather than sleep - check your power cord. But if this doesn't correct it, I will try what you wrote in your post. Thanks.

 

[seabreeze56]

Well it's NOT the power cord. Got up this morning and the dang thing is shut down again. So I did as you suggested above and we shall see if it continues. It seems to stay in sleep mode during the day. It's over night when it shuts down. And when I re-start it with the power button, it's acting as if it was shut down incorrectly. I have a 90 day warranty so it might have to go back - IDK. I've read that things were buggy in El Capitain but it's running on Mojave.

 

[seabreeze56]

Ok so I did everything above that was suggested and it's still not staying in sleep mode - shuts down. I checked to see if filevault is off and it is so it's not that. Any other suggestions. I guess it's going to get sent back because i'm out of ideas.

 

[seabreeze56]

I remember my macbook pro doing this same this but in high sierra. I upgraded to Mojave and it stopped and working fine. So the imac desktop is doing this irritating thing in Mojave. I'm now upgrading it to Catalina and see if it doesn't fix this. If not, I may go to the dark side - PC. Because this is beyond annoying!