How to Run Diagnostics on a Mac: A Step-by-Step Guide

Start Apple Diagnostics Press and hold the power button on your Mac. (Every Mac has a power button. ... As you continue to hold the power button, your Mac turns on and loads startup options. When you see Options, release the power button. Press and hold Command (⌘)-D on your keyboard.
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If you suspect that your Mac may have a hardware issue, Apple Diagnostics can help you determine which hardware component might be at fault. In this article, we will show you how to run Apple Diagnostics on both Intel processor-based Macs and Apple silicon-based Macs.

Before running Apple Diagnostics, you’ll need to prepare your Mac by disconnecting all external devices except for your keyboard, mouse, display, Ethernet connection (if applicable), and connection to AC power. Also, make sure that your Mac is on a hard, flat, stable surface with good ventilation.

For Intel processor-based Mac machines, there are two possible ways to run Apple Diagnostics. The first is by using the command line, and the second is by using the keyboard shortcut method. Before proceeding with any of the methods, make sure that your Wi-Fi is enabled or you have a working Ethernet connection on your Mac.

To run Apple Diagnostics using the command line, open Terminal and execute two commands one by one. After executing the second command, your Mac will reboot, and Apple Diagnostics will load. After connecting to a working Wi-Fi network, you’ll be presented with two options. By selecting “I agree,” you acknowledge that Apple may collect, use, and retain your information for diagnostic and support purposes, as well as to improve its products. If you do not want Apple to collect this information, select “run offline” or press the Escape key, and your diagnostic will be started.

After testing is complete, Apple Diagnostics displays the results, including one or more reference codes. You can learn more about the reference codes shown in Apple Diagnostics test results by clicking on the “get started” link or checking the description below.

To run Apple Diagnostics using the keyboard shortcut method, turn on your Mac and immediately press and hold the D key on your keyboard as your Mac starts up. Release the key when you see a progress bar or you’re asked to choose a language. After connecting to a working Wi-Fi network, Apple Diagnostics will load, and you can select your language and proceed.

For Apple silicon-based Macs, there is only one way to run Apple Diagnostics. You’ll need to boot your device to Startup Manager by turning on your Mac and continuing to press and hold the power button as your Mac starts up. Release the key when you see the startup options window, which includes the gear icon labeled “options.” To initiate Apple Diagnostics, press and hold Command + D on your keyboard until the diagnostics start. After connecting to a working Ethernet or Wi-Fi network, select your language and click “OK.”

After running Apple Diagnostics, you can learn more about the reference code shown in the results by clicking on the “get started” link or checking the description below. We hope this guide was useful to you. If you have any questions, please comment down below. Thanks for reading, and have a great day ahead.