iMac 5k 2017 fan turns on when in sleep mode.

[Miguel.frigola]

Hi guys, on first, sorry for my English, I need help about this, the fan of mi new iMac (3,5 i5, 8gb ram) turns on when the computer are in sleep mode, only for a few seconds and at the lowest rpm, the screen keeps off, someone have the same issue or knos how to fix it? I restart de SMC system, and I run the apple diagnostic keep the D key, and all is correct. THANKS

 

[Brookzy]

This is probably Power Nap.

https://support.apple.com/en-gb/HT204032

You could try turning it off in System Preferences > Energy Saver, and then seeing if the fan goes away.

If the fan doesn't bother you, Power Nap is very useful.

 

[casperes1996]

Yep. Sounds like PowerNap. Mine does it too - especially for Time Machine backups.

 

[Miguel.frigola]

I deactivated power nap and I kept doing it, finally I restore all system and downgrade to Sierra 10.12.6, everything runs perfect now, thanks for all guys I will upgrade to High Sierra again soon, when the software runs perfect

 

[casperes1996]

I deactivated power nap and I kept doing it, finally I restore all system and downgrade to Sierra 10.12.6, everything runs perfect now, thanks for all guys I will upgrade to High Sierra again soon, when the software runs perfect

Did/Do you have any devices connected to it, like USB hard drives, mice, etc.? They can also activate the computer when it's sleeping. In the battery section of system prefferences there's also a toggle for allowing wake on network access (Think it's in the battery section anyhow)

 

[Miguel.frigola]

Did/Do you have any devices connected to it, like USB hard drives, mice, etc.? They can also activate the computer when it's sleeping. In the battery section of system prefferences there's also a toggle for allowing wake on network access (Think it's in the battery section anyhow)

Anyone bro ..... i don't understand it.