iPhone 6/6+ - Error 53
Regarding Error 53, we've found that the issue is sporadic and doesn't affect all replacement parts, however when it does occur we suspect it may be an issue related to a new home button link cable (which frequently comes preinstalled on new full display assemblies). But, it is possible that a damaged part could cause the error since it's no longer recognizable to the OS.
Here are some articles in which we go into more depth regarding the topic:
- http://ifixit.org/blog/7889/whats-up-with-error-53/
- http://ifixit.org/blog/7900/repair-error-53/
- http://ifixit.org/blog/7911/error-53-iphone-6s/
In order to restore functionality, try using the original home button link cable. Otherwise, try reverting to the original display assembly (including original home button link cable) and the original home button assembly, then perform the update. Once the update is successful, then you can try reinstalling the new part(s).
For the iPhone 6, please refer to this guide here regarding the home button link cable. For the iPhone 6 Plus, we don't have an explicit guide, but the process is similar to the iPhone 6.
Please Note: Apple also now has a support page detailing what to do now when you receive Error 53. After applying the update, the difference now is that the error will no longer brick the device and it can be recovered from. Recovering from Error 53 in this manner reverts the device to no longer use the Touch ID sensor (just like the iPhone 5S), but you can still use it as a basic home button (like the iPhone 5) and ApplePay will be disabled. If you paid for an out of warranty device, you are potentially eligible for reimbursement from Apple, but have to contact Apple Support.