Apple has released a new version of iOS 9.2.1 with build 13D20 to resolve error 53 in iPhone. Error 53 bricked certain models of iOS devices which got Touch-ID repaired by unauthorized repair shop.
Fix Error 53 By Updating to iOS 9.2.1 build 13D20
iOS 9.2.1 is the same firmware which was released by Apple last month with build number 13D15 and there are no new features. Apple has updated iOS 9.2.1 to build 13D20 which patches error 53 error for the latest devices. The latest update of iOS 9.2.1 is not available for all devices unless you are facing error 53 on Touch-ID compatible devices.
The latest iOS 9.2.1 build 13D20 is not OTA and can be installed only via iTunes. Make sure that you have installed the latest version of iTunes to install the new version of iOS update.
To install the latest IPSW via iTunes
Connect your device to your computer.
Select the device in iTunes.
Windows users hold down “SHIFT” key and then click on “Update” whereas, Mac users hold down the “Option” key and then click on “Update”.
Select the IPSW file you downloaded and click “Choose”
Device will get updated.
Download iOS 9.2.1 Build 13D20