Hello there, chapkit.
When having issues waking a Mac from sleep, the following Knowledge Base article offers some great, in-depth information for troubleshooting:
OS X: When your Mac doesn't sleep or wake - Apple Support
Start with the recommendations found here:
Your computer cannot wake from sleep
Make sure your computer isn't powered off by pressing the power key for one second.
If you're using an external display, make sure your display is not powered off or unplugged.
If you are using a Mac notebook:
- Make sure the computer's battery is charged. Try connecting the power adapter to the computer, then press the power button for one second to see if the computer powers on.
- Make sure the AC power cord is connected securely to the power outlet, and that the outlet it is working correctly. Confirm the power adapter or cable is attached firmly.
- If your computer is plugged into a power strip, make sure the power strip is not turned off. Check to make sure other items connected to the power strip are receiving power.
- Confirm the right power adapter is connected on Mac notebook computers. If a lower wattage power adapter is used than the one that came with your Mac, it may not provide enough power to charge the battery while the computer is powered on. Make sure there is no debris in the MagSafe port that might prevent charging. When your MagSafe cable is connected properly, you should see a green or orange light on the connector.
Your computer is slow to wake from sleep
If you see a progress bar when you wake your computer from sleep, this is normal. The computer is waking from safe sleep.
OS X Recovery and sleep
The system software your computer uses when started from OS X Recovery allows display sleep. Your computer does not go to sleep on idle while started from Recovery unless you are using a Mac notebook that is not connected to AC power.
If your issue persists, after trying those steps, proceed with:
Reset SMC
The System Management Controller (SMC) is involved in managing power on your computer. Reset the SMC on your Mac if you are having difficulty sleeping or waking your computer.
Reset NVRAM/PRAM
Nonvolatile RAM (NVRAM)/Parameter RAM (PRAM) stores some power-related settings.Try resetting NVRAM/PRAM if you are having difficulty sleeping or waking your computer.
Test with external devices disconnected
Some external devices can prevent your computer from sleeping. Try disconnecting items other than your Apple keyboard or mouse from the built-in USB, Thunderbolt and Firewire ports on your Mac. If this resolves the issue, try reconnecting your external devices one at a time until you find the device preventing sleep or wake. Check the documentation that came with the device, or contact the device manufacturer for more information.
Try Safe Mode
Check to see if the issue still occurs when the computer is started in Safe Mode. If this resolves the issue, it could be related to a third party software item such as:
Try another user account
Try creating another user account, or log in as guest. See if your computer sleeps and wakes properly from the additional user account. If it does, your issue may be related to one of the following:
You can disable login items from the Accounts pane of System Preferences. Try opening only one app at a time in the original user account to determine which app is preventing sleep. If you isolate the issue to a particular app or login item, check its documentation, or contact the developer of that software for more information.
Thanks for reaching out to Apple Support Communities.
Kind Regards,
Pedro.