Error 53 and Error 56 mean your biometric sensor is damaged or mismatched with the logic board.
Important: Touch ID and Face ID are factory-paired to the logic board. Non-original replacements trigger these errors. Only Apple can re-pair a new sensor.
Error 53 — Touch ID damaged
Physically damaged, disconnected, or replaced with non-original part. Water damage is a common cause.
Workaround: DFU restore to iOS 9.2.1+ lets the iPhone boot, but Touch ID will be permanently disabled. The phone works normally otherwise.
Error 56 — sensor mismatch
Serial number mismatch between sensor and logic board. Almost always means a third-party repair shop replaced the sensor. Only Apple can resolve this by re-pairing a genuine sensor.
If none of the above works, the issue is most likely physical hardware damage — a failing chip, corroded connector, or broken internal component. If you've tried everything above and the error keeps coming back, the problem is most likely physical — something broken inside the device that software can't fix. That's when it needs professional hands-on inspection.