My fingerprint sensor on my iPhone 5s is not working, but the home button is working. I want to replace the fingerprint sensor. Is it possible to just buy a new fingerprint sensor - home button assembly and replace it, and will it just work? I heard stories that fingerprint sensor is somehow hard wired with the motherboard and no other fingerprint sensor can replace the original one. Is this true?
The only way to replace or repair the fingerprint sensor is for Apple to do it for you.
It is tied to the secure enclave in the CPU & any unauthorised tampering will disable it.