A chance to revive hard bricked devices..
Here's a thread discussing a way to repair hard bricked Xperia Z Ultra and Xperia Z1:
The tool used here doesn't support Qualcomm APQ8064 (Z & ZL) yet but the developer said, he'll add support if there will be enough requests.
So, if you own a hard bricked Z or ZL (hard bricked means: no fastboot mode, no flash mode working) and you can't send it to service center,
you know what to do..