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My iMac is not going to screen savers or sleep
- Thread starter levmc
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Try disconnecting every mouse, trackpad, or other cursor-positioning input device. Sometimes they can generate tiny "move" signals that fool the OS into thinking that input is happening. This will prevent screen-saver or sleep. The signals might not be enough to move the cursor, but they can still prevent sleep.
If the problem continues after they've all been disconnected, make sure you don't accidentally have a wireless input device paired, because it might also be generating spurious inputs. A typical example is a Bluetooth mouse kept in a backpack, that's accidentally turned on.
If it still continues, please post a list of all the USB input devices listed in the System Info.app under the USB pane. There's also a way to get the list using a command-line tool in a Terminal window, but I'd need to look up the details. It's simpler if you expand the list of USB devices and post a screenshot of it.
If you have Bluetooth devices, there's also a Bluetooth pane in System Info.app.
If the problem continues after they've all been disconnected, make sure you don't accidentally have a wireless input device paired, because it might also be generating spurious inputs. A typical example is a Bluetooth mouse kept in a backpack, that's accidentally turned on.
If it still continues, please post a list of all the USB input devices listed in the System Info.app under the USB pane. There's also a way to get the list using a command-line tool in a Terminal window, but I'd need to look up the details. It's simpler if you expand the list of USB devices and post a screenshot of it.
If you have Bluetooth devices, there's also a Bluetooth pane in System Info.app.
Start by opening System Info.app. For a Big Sur example, see here:
The different panes are activated by clicking the names in the left-hand sidebar. You can see Bluetooth and USB in the sidebar of Apple's screenshot.
I'm pretty sure that app resides in Applications/Utilities, but it would help narrow things down if you told us which OS you're using, and which Mac model it is.
System Information User Guide for Mac
In System Information on your Mac, create a system report.
support.apple.com
The different panes are activated by clicking the names in the left-hand sidebar. You can see Bluetooth and USB in the sidebar of Apple's screenshot.
I'm pretty sure that app resides in Applications/Utilities, but it would help narrow things down if you told us which OS you're using, and which Mac model it is.
Aside on mouse pointer movements, the other explanation might be that there's software that prevents sleep
Simple things like a video playing or even a pop-up notification that insists one being clicked on can be enough to prevent screensaver/sleep to happen.
I've seen a few times some of my macs not go to sleep as they should. Usually a reboot solves it :-(
You can force a screensaver to start
e.g.: https://support.apple.com/en-mn/guide/mac-help/mchlp3000/10.15/mac/10.15
You can also force sleep yourself:
> Sleep (or on a laptop: close the lid assuming it's got no external keyboard etc.)
Simple things like a video playing or even a pop-up notification that insists one being clicked on can be enough to prevent screensaver/sleep to happen.
I've seen a few times some of my macs not go to sleep as they should. Usually a reboot solves it :-(
You can force a screensaver to start
e.g.: https://support.apple.com/en-mn/guide/mac-help/mchlp3000/10.15/mac/10.15
You can also force sleep yourself:
> Sleep (or on a laptop: close the lid assuming it's got no external keyboard etc.)
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