Why Mac is not sleeping properly?

In this digitized world, after a tired work schedule, everybody wants to have proper rest for a period of time. On the other hand, If we talk about electronic devices like Windows PC, Mac system or iMac machine then the question arises, do they need rest? The answer is yes! Yes, there is a need to make them sleep to save the power/energy.

There are different ways to make Mac in sleep mode like

• Leave the system inactive for longer time than specified as earlier in ‘System Preference’ and Energy Saver pane
• Choose ‘Sleep’ from the Apple menu
• Pressing the power button and choosing sleep option
• Closing the display lid of a portable system

Generally, we make a setting of ‘sleep mode’ for our machine to sleep after 20 minutes or 30 minutes of inactivity; but sometimes, it doesn’t do the same even after closing the lid. Many of us must have faced this issue of Mac waking up by itself before the set time period or keep sleeping for a long time.

Although, there are many circumstances that keep charging Mac to either keep sleeping or waking up. But it is a bit difficult to find and resolve those because there are many jobs like accessing a file on the network, downloading a file or disconnecting a shared printer with an open file or folder etc. are here which don’t allow Mac to sleep. Let’s figure out what the causes might be in Mac and how to troubleshoot as well to optimize Mac.

Just suppose, if Mountain Lion is running then, make sure that ‘Energy Saver’ slider is set properly as you wish by navigating through System Preferences> Energy Saver in Mac. Few Mac users are in the habit of using Mac via network access with shared resources then you can disable network wake by going to System Preferences> Energy Saver, and uncheck the option for “Wake for Wi-Fi Network Access.”

 

Energy saver slider

Additionally, Bluetooth devices are also in the same scenario to make Mac wake up instantly by just a click or pressing of button. So these Bluetooth peripheral devices like keyboard, trackpad or mouse must be switched off when Mac is not in use.

There are many apps which don’t allow Mac to sleep by accessing the disk most of the time to exhibit the user instructions like iTunes which access disk to read and play the songs and DVD player accesses the Optical Disc to play movies. An automated running backup is also another way to stay Mac away from a proper sleep.

Sometimes, Spotlight feature is active at indexing the hard disk for checking the files. You can check by clicking on Spotlight icon on the right side of menu bar and if it is busy at indexing the Mac HDD then it won’t let the Mac to sleep for a long time.

Moreover, Malfunctioning USB peripherals, FireWire, and Thunderbolt devices restrict Mac from going to sleep. To let Mac for sleep, disconnect these devices one later on, if it needed then re-connect one by one at a time to use and check which one malfunctions.

Generally, we use PCI extension cards in combination with PCI Express riser cards on a computer motherboard to facilitate PCI card mounting. Few PCI extension cards don’t allow Mac for sleep and keeps waken up intentionally. If you are facing this issue the please see the documentation that came with the PCI extension cards. 

PCI Extension Card

Once you check all then you can type a command in Terminal and analyse

pmset –g assertions

This command will inform you about those devices and process which are preventing Mac from going to sleep.

Try all the above mentioned tips to give your Mac a proper sleep and save the energy along with the resources.