iPhone and Android: Face ID or fingerprint not working

Face ID and fingerprint unlock are convenient, but they can stop working when something changes, such as a new case, a cracked sensor or damp fingers. In most cases the fix is straightforward.

Quick checks

1. Clean the sensor. On iPhone, wipe the notch area at the top of the screen. On Android, wipe the fingerprint sensor, whether it is on the screen, the back or a side button.
2. Remove any screen protector that covers the sensor. Some thick or poorly fitted protectors interfere.
3. Dry your fingers. Wet, greasy, dirty or very dry skin all cause misreads.
4. Restart the phone.

Face ID on iPhone

• Hold the phone at a normal reading distance, roughly arm's length, and look at the screen.
• Make sure nothing covers your eyes, nose and mouth, such as a mask or some sunglasses.
• Check Settings then Face ID and Passcode. Make sure iPhone Unlock and any apps you want are on.
• If it still fails, go to the same screen and tap Reset Face ID, then set it up again. You will need your passcode.
• Face ID needs the passcode after a restart, or after several failed tries. This is normal security.

Fingerprint on Android and other phones

• Open Settings and look under Security or Biometrics (the wording differs between Samsung and Pixel).
• Delete a poor fingerprint and add it again. Press down the way you normally hold your phone.
• Add the same finger twice, using different parts of the fingertip. Many people find this improves reliability.
• Try again without a case or protector.

Why you may be asked for your PIN

Phones ask for your passcode after a restart, after not unlocking for a day or so, or when security settings change. This is normal.

When to get more help

Get help if the fingerprint sensor does not respond at all after a screen repair, if Face ID says it cannot be used after trying everything above, or if you see a message that the TrueDepth camera needs attention. A camera or sensor can be damaged by a drop or water.