Your Mac will go to sleep after a specified duration of inactivity, automatically. You can also put your Mac to sleep when you choose Apple Menu > Sleep. You can change your computer’s sleep settings by going to System Preferences > Energy Saver, so that you can tell your Mac how long to wait before it goes to sleep. Are you having problems where macOS won’t go into sleep mode when expected? This article explains how you can troubleshoot it. So why your Mac is not sleeping.
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It is important that your Energy Saver settings is set up the way you want. You can check this by going to System Preferences > Energy Saver.
1-First let’s try to figure out what is preventing your Mac from going to sleep. Some internal activities may keep your Mac wake. For example, several users have said that their printers (e.g., pending print jobs) cause this. Here is how you can see this:
- First launch the Activity Monitor app (Applications > Utilities) or you can open Spotlight (Spotlight not working?) and search for it.
- Click the Energy pane.
- There are five or six column and and one of them is called “Preventing Sleep”. This column indicates what processes prevent your Mac from going to sleep. As you can see below, iTunes is keeping the Mac wake, meaning it is interrupting Mac sleep mode. Because iTunes is open. Try closing this app. As long as this app is open, the Mac will not go to sleep automatically.
2-You can also use the Terminal app to determine the cause of sleep prevention. Here is how:
- Launch the Terminal app (Applications > Utilities)
- And enter the following command and hit enter:
- pmset -g assertions
- And read the results. It will produce something like this:
Assertion status system-wide:
Try to find items with a “1” next to them. As you can see PreventUserIdleSystemSleep has 1 thus it is enabled. Check under the “Listed by owning process” line. The results will also give more details, as you can see below:
Listed by owning process:
pid 12558(iTunes): [0x00009cf70001a498] 00:00:12 PreventUserIdleSystemSleep named: “com.apple.iTunes.playback”
pid 157(coreaudiod): [0x00009cf70001a48c] 00:00:12 PreventUserIdleSystemSleep named: “com.apple.audio.AppleHDAEngineOutput:1B,0,1,1:0.context.preventuseridlesleep”
This explains that iTunes is the cause.
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3-If you are still having issues, try resetting NVRAM or PRAM. Resetting NVRAM and PRAM are same. Some display settings are stored in NVRAM and resetting this may resolve your issue. Here is how:
- Turn off your Mac
- And turn on your Mac and immediately press and hold the Option, Command, P, and R together for about 20 seconds. Your Mac will look like restarting.
4-Still no luck? Then reset SMC on your Mac. Resetting SMC is more complex than resetting NVRAM. Apple documentation clearly explains this process.
If you are still having issues, you may want to contact Apple.
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