Accessing Mac Hardware Diagnostics Mode (#1417)



http://macmost.com/e-1417 If something is wrong with your Mac, either you or the tech repairing your Mac will need to access the special diagnostics mode. You can do this by restarting your Mac and holding the D key. The results could give you some insight into the problem. See https://support.apple.com/en-us/HT202731 for details.

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