Intel Macs tell you why they last shut down, in the ‘shutdown cause code’ written to the log by their System Management Controller. What do Apple silicon Macs do?
cause code
You discover your Mac has either restarted itself and is waiting for you to log in, or has simply shut itself down. How to find out why this happened, in Intel and Apple silicon.
Shutdown cause codes, wake reasons, ACPI, and sleep states – diagnosing problems from hardware events.
Waypoints to help you navigate through Sierra’s log entries when putting a Mac to sleep, and when waking up from sleep.
How to interpret the code numbers written into your Mac’s log to indicate the reason for shutting down, restarting, or going to sleep.
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