SMC, or System Management Controller, is a chip available for Intel-based Macs or iMacs that controls and stores critical details of different hardware functions. Since we are talking about screen brightness, try to reset the SMC of your Mac or iMac to see if it solves the problem.
Note: SMC reset is not applicable for Mac models running on M-series chips. Restarting these Macs itself acts like the process of SMC reset.
Step 1: Press and hold the Power Button until your Mac shuts down.
Step 2: After your Mac shuts down, wait for a few seconds and press Shift Left Option Left Control key. Press and hold the Power Button too.
Step 3: Keep pressing the four keys for another 7 seconds. If your Mac turns on, it will play the default start-up chime again while you hold down the keys.
When you see the Apple logo, the display will turn on normally. But if it doesn’t boot after the Apple logo, check the next solution.
Another solution for Intel-based Macs is performing an NVRAM reset. NVRAM, or Non-Volatile Random Access Memory, holds information like sound volume, startup disk selection, time zone, and more. If you can’t get the display to turn on after sleep on your Mac, try to reset the NVRAM. Do note that after the NVRAM reset, you must adjust these settings again on your Mac.
Step 1: Long-press the Power Button on your Mac.
Step 2: After your Mac shuts down, press the Power button again to boot your Mac.
Step 3: While your Mac is turning on, press Option Command P R for 20 seconds.
Step 4: Release all four keys when the Apple logo appears for the second time. This means that the NVRAM reset is complete. After that, your Mac will restart.
Step 5: Check if the display is turning back on or not.
Note: The NVRAM reset is only applicable for Intel-based Macs. Restarting a Mac running on an M1, M2, M1 Pro, or M1 Max chip is equivalent to performing an NVRAM reset.
For external displays, try replugging it with your MacBook and manually detect it again.
Open Settings > Displays > press the Option key > click on Detect Displays.
If your external display is working after connecting to the Mac, try disabling this feature for some time and see if the problem is solved.
Step 1: Open Settings > Battery > Options.
Step 2: Disable the toggle for Prevent automatic sleeping on power adapter when the display is off.
The above is the detailed content of 4 Ways to Fix Mac Display Not Working After Waking From Sleep. For more information, please follow other related articles on the PHP Chinese website!