

Moreover, your Mac that stops entering sleep mode can also be caused by:

If you shut off the notebook lid with your MacBook connecting to power, your MacBook Pro that fails to go to sleep when the lid is closed may be caused by the enabled sharing accesses, like Internet, Printer, Bluetooth, or other access. There are diverse reasons why your Mac is disordered in switching between sleep and normal mode when closing the lid. Why your Mac won't go to sleep when the lid is closed? FAQ about Mac won't go to sleep when lid closed Mac won't go to sleep when the lid is closed, how to fix it?

Here we go to learn about the reasons and try the ways. This post is a full guide that supplies the quick and efficient workarounds to fix the MacBook Air, MacBook Pro, and M1 Mac not sleeping when lid closed issue. This issue is awful as it will drain your battery fast and reduce the life of your machine. True, your Mac won't go to sleep when the lid is closed. And when you open the lid, the MacBook just stays on the Desktop rather than shows the login screen. You can see the light from the sides of the Mac. By default, your MacBook will go to sleep when you close the laptop lid.
