The Error 53 issue that iPhone 6 owners who have upgraded their Touch ID sensors are seeing is not a bug, but a security feature, says Apple.
In a statement to ZDNet, an Apple spokesperson had this to say:
"We take customer security very seriously and Error 53 is the result of security checks designed to protect our customers. iOS checks that the Touch ID sensor in your iPhone or iPad correctly matches your device's other components. If iOS finds a mismatch, the check fails and Touch ID, including for Apple Pay use, is disabled. This security measure is necessary to protect your device and prevent a fraudulent Touch ID sensor from being used. If a customer encounters Error 53, we encourage them to contact Apple Support."
This is an expansion on the statement that Apple had given The Guardian earlier today.
While it's good to know that Apple is taking user security seriously, bricking users' handsets without warning seems a little extreme. Perhaps an on-screen warning that Touch ID may have been compromised would suffice?
There's also evidence to suggest that Error 53 might not only be generated by a third-party replacement of the Touch ID sensor. Mike Wehner of The Daily Dot claims that he was hit with the problem after having issues with the fingerprint reader. Apple agreed to replace Wehner's iPhone.
But be in no doubt that if your Touch ID sensor has been replaced anywhere other than an at an Apple authorized repair center, Apple is not going to be handing you a free iPhone.
iFixit's Kyle Weins believes that third-party repairers need to have a way to pair new Touch ID components with handsets.
"If you lock your keys in your own car, AAA can open it back up for you," writes Weins on the iFixit blog. "If you lock yourself out of your house, a locksmith can get you back into it. No one is going to make you throw your apartment away because they're afraid of the locksmith. Their ability to unlock things for owners doesn't pose an unnecessary security risk."
Moral of this story: If you have an issue with the Touch ID sensor, you must get it fixed by an authorized Apple repair center.