[Q] Xperia Z (very deep) sleep of death

[LucaFraga]

Hi everyone, a friend of mine bought an used Xperia Z and replaced the battery with a brand new one. Problem is that after a while of flawless usage, the battery drained to 0% and the phone refuses to charge or power on at all, this is the situation so far:

BATTERY PLUGGED:
- Cable on: can't go to flash mode or fastboot, the phone tries to power on and gets detected for a split second (screen off and red light ever so often)
- Cable off: fully dead

BATTERY UNPLUGGED:
- Cable on: can go to flash mode and fastboot mode (this way I flashed latest official ROM) but doesn't boot of course
- Cable off: of course nothing.

What I tried so far:
- Charging overnight, NO USE
- VOLUME+ and POWER ON for 8 secs, then charge for 1 hour, NO USE
- Hot plugging the battery with the cable off (bad idea), MANAGED TO BOOT ONE TIME but like an idiot i disconnected the cable to switch to wall charging

Does any of you have any idea? Of course the phone is out of warranty and I don't have another Xperia Z to charge the battery, neither I think another battery will help, since this works.

 

[VIVAS700]

im having this same issue, ive even tried a replacement battery with no results.
ive asked around in the Sony forums and my posts either get ignored or deleted seems like this is probably my first and last sony phone.