Ever since December of 2013, a large number of Sony Xperia Z1 and Z Ultra owners began to experience what has been dubbed and feared as an Xperia “Brickademic.” This issue that has garnered confused, angry, and disappointed responses spanning over more than 35 pages in the discussion thread, and the cause seems to be spawning from kernel incompatibilities that result from flashing an Android 4.3 firmware on a device running certain builds of Android 4.2.2. Now that it has been festering for a couple of months already, XDA Forum Members vovanx500 and the_laser have finally come out with a solution to the bricking problem.
Vovanx500 makes it clear at the beginning of the tutorial that the fix is not for the faint of heart, with the process requiring disassembling your device, which voids your warranty, in order to access the testpoint. The tutorial lays down the necessary steps to recover your bricked device, from guiding you on what has to be done once you’ve removed the back cover of your device, to running the actual program and finally getting the device back on track. The fix would not be possible without the efforts of the_laser, who developed the program used in the process, as well as vovanx500’s Xperia Z Ultra which was used as a guinea pig to find the testpoint.
This definitely isn’t a fix that everyone may want to try due to its complexity. But if you’re willing and have the nerve, head over to the original thread for more information.
[Thanks to Senior Member zeppelinrox for the tip!]_________