Digitizer assembly replacement and Error 53
Apple has released a fixed version of iOS 9.2 (specifically 9.2.1 and later) which will restore the device to operation.

It doesn't fix the touch sensor - but you can use the device.

https://support.apple.com/en-us/HT205628

Also see:

Error 53 makes my sister&#39;s iPhone 6 brick

So - if you disturb/tamper with the touch sensor - you won't brick the device when updating from iTunes (as opposed to an OTA update which doesn't throw error 53 for iOS 9.2 and lower), but the sensor won't work going forward.