How to Run Apple Diagnostics on a MacBook (and Read the Results)

When your MacBook restarts randomly, won't charge, or behaves in ways that software fixes can't explain, it's time to test the hardware. Apple Diagnostics is built into every modern Mac, and running it on your MacBook takes just a few minutes. It checks components like the battery, memory, logic board sensors and power circuits, and gives you a reference code you can use to understand what's going on.

Before you start

1. Back up your data if the Mac is still usable. Diagnostics doesn't erase anything, but if it finds a fault, a repair may follow.
2. Disconnect external devices except the keyboard, mouse, display, Ethernet connection and power adapter, if you use them.
3. Place the Mac on a hard, flat, well-ventilated surface and plug in the charger.
4. Check which Mac you have: Apple menu > About This Mac shows "Chip" (Apple silicon) or "Processor" (Intel). If you're not sure of the exact model, our guide on finding your MacBook model and year helps.

Run Apple Diagnostics on Apple silicon (M1, M2, M3, M4)

1. Shut down your MacBook.
2. Press and hold the power button until the startup options window appears.
3. Release the power button.
4. Press Command-D on your keyboard.
5. Follow any on-screen instructions. Diagnostics runs automatically.

Run Apple Diagnostics on an Intel MacBook

1. Shut down your MacBook.
2. Turn it on and immediately press and hold the D key.
3. Release D when you see a progress bar or you're asked to choose a language.
4. If holding D doesn't work, try holding Option-D at startup to load Apple Diagnostics over the internet (Wi-Fi or Ethernet required).

Reading the results

When the test finishes, you'll see either "No issues found" or a description of the problem along with one or more reference codes.

• ADP000 means no issues were found.
• Other codes point to a specific area, such as the battery, memory, a sensor, the fan or power circuits. Write the code down or take a photo of the screen.
• Some tests let you repeat the check by clicking "Run the test again". You can also restart or shut down from the results screen.

Keep in mind that Apple Diagnostics is a basic test. A "no issues found" result doesn't guarantee your hardware is perfect; intermittent faults, liquid damage and some board-level problems may not show up. If the problem continues, the code and the symptoms together help a technician diagnose it faster.

What to do next

• No issues found, but the Mac still misbehaves: try starting in Safe Mode to rule out software, then update or reinstall macOS.
• Battery-related code: check the battery condition in System Settings > Battery (or System Preferences > Battery on older versions). A battery replacement may be needed.
• Fan or sensor code: the cooling system or a sensor may need attention, especially if the Mac runs hot or loud.
• Memory, logic board or power codes: these usually need professional, board-level repair.

Need MacBook repair in Ottawa?

If Apple Diagnostics found a problem, or your Mac won't even start the test, Fix Revolution can take it from there. With more than 10 years repairing Macs and board-level repair and micro soldering in-house, we fix problems many shops send away. We pick up and drop off anywhere in Ottawa and Gatineau, and quotes are free. For MacBook repair in Ottawa, get a free quote or call 613-265-4349 and share your reference code.

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