Apple Diagnostics is a built-in tool that helps MacBook users check for potential hardware problems. It can test internal components such as the display, keyboard, trackpad, memory, batteries, cameras, storage, and wireless hardware. Before using the tool, users should determine if their MacBook uses Apple silicon (like the M1 or M2 chip) or an older Intel processor. This can be checked in the system information settings. To run Apple Diagnostics on a MacBook with Apple silicon, users need to press and hold the power button (or Touch ID button) until the startup options screen appears, then press and hold the Command (⌘) and D keys. For Intel-based MacBooks, users should press and hold the D key immediately after turning on the machine. If that doesn’t work, they can try pressing and holding both the Option (⌥) and D keys to run the diagnostics over the internet. It’s important to note that Apple Diagnostics only checks internal hardware and does not identify issues caused by the macOS operating system, apps, or software extensions. A clean test result, shown by the reference code ADP000, means no hardware problems were found during the test. However, this does not eliminate the possibility of software or external accessory issues. If specific reference codes are displayed, users can look them up on Apple’s website to find out which component is affected and what steps to take next. If Apple Diagnostics doesn’t find any hardware issues but the MacBook still has problems, users may want to use macOS Recovery. This tool provides options to repair the startup disk, reinstall macOS, or restore from a Time Machine backup. The steps to access macOS Recovery differ slightly between Apple silicon and Intel MacBooks, so users should follow the appropriate instructions based on their device’s processor type.