Diagnostics Mode
Is that shiny new M1 Mac acting flaky? To check the hardware to see if you’re having any issues, diagnostics mode is very useful.
Shut down your Mac, then press the power button to start it up again. Keep holding the power button until the display shows Loading Startup Options. When the Startup Options screen fully loads, you’ll see a “gear” icon with the label Options beneath it. There are also icons for the internal and external drives. Press and hold Command ( ⌘ ) – D until the Mac restarts and the Diagnostics Loader menu appears in the menu bar.
A list of languages appears – highlight the language you need, then click the blue OK button. At this point, a screen titled “Run Diagnostics” appears (see image below), displaying a barcode with your Mac serial number, a Restart button, and a Shutdown button. In addition, there are links for Run offline and I agree.