As macOS gets more complex, diagnostic and control tools provided by Apple have become less accessible. This makes macOS harder to diagnose and support.
diagnostics
Shutdown cause codes, wake reasons, ACPI, and sleep states – diagnosing problems from hardware events.
One of the original reasons for my tools to open access to macOS Sierra’s new unified log system […]
This new version adds a Help Book, Tooltips, and supports window resizing more usefully.
How to run Apple’s diagnostic software to work out whether your Mac has a hardware fault – and how to interpret its error codes.
This new version includes its docs as a Help Book, and adds Tooltips to explain the output and controls.
Two major tools are available to help you deal with problems. Here’s how to use them to best effect.
Browsing existing log entries in macOS Sierra is now much easier and more powerful.
This may help you work out what is going wrong with local keychains in Sierra. Another free tool to spare you from Terminal.
Here’s a new version of this utility to check whether SIP and other security systems are active.
The Eclectic Light Company 