How to diagnose a mechanical problem on the iPhone 16

Six categories of mechanical failures

Apple distinguishes between alert messages (overheating, liquid detection, accessory compatibility), sensor malfunctions (ambient light, proximity, compass affecting the display), button and switch failures (side button, volume, Action button), issues related to the home button and Touch ID, SIM card errors, and vibration issues (Taptic Engine).

What's normal and doesn't need a repair

An important point: occasional temperature alerts or occasional Touch ID trouble with certain fingers (related to skin condition, for example after washing your hands) are normal and don't signal a fault that needs fixing.

The diagnostic method to follow

As with the other categories, the approach is progressive: cleaning and restarting first, then the software diagnostic suite (MRI), then a physical inspection of internal components, and replacing the relevant part only as a last resort.

Symptoms that justify a check

Buttons that no longer respond, missing vibration, a screen that doesn't adjust to ambient light, a proximity sensor that doesn't turn off the screen during a call, or a visibly misaligned or damaged button are the signs that do deserve a deeper check.