Shut down your Mac by choosing Apple menu > Shut Down, then press the power button again to turn on your Mac.Restart your Mac by choosing Apple menu > Restart.Wake the computer after it’s gone to sleep. Put your Mac to sleep by choosing Apple () menu > Sleep.Press Command-Option*-Escape to force quit any application that’s not responding.Then press the power button again to turn on your Mac. You’ll lose unsaved work in any open applications. If your Mac isn’t responding, press and hold the power button until it shuts down.Test the issue after each step to see if the issue still occurs.

Try each of these steps in this order before you reset the SMC.

The illumination around the I/O ports on a Mac Pro (Late 2013) doesn’t turn on when you move the computer.

A Mac that supports target display mode doesn’t switch into or out of target display mode as expected, or it switches into or out of target display mode at unexpected times.

Your Mac performs unusually slowly, even though its CPU isn’t under an abnormally heavy load.

The MagSafe power adapter LED, if present, doesn’t indicate the correct charging activity.

Your MacBook or MacBook Pro doesn’t recognise external devices that are connected to its built-in USB-C port.

Your MacBook or MacBook Pro doesn’t charge through its built-in USB-C port.

The display backlight doesn’t respond correctly to ambient light changes.

Your Mac sleeps or shuts down unexpectedly and you can’t turn it back on.

Your Mac notebook doesn’t respond properly when you close or open the lid.

Your Mac doesn’t respond when you press the power button.

Battery indicator lights, if present, behave incorrectly on Mac notebooks with a non-removable battery.The status indicator light, if present, behaves incorrectly.The keyboard backlight behaves incorrectly.

Your computer’s fans run at high speed, even though it isn’t under heavy usage and is properly ventilated.

Restart macbook air using keyboard