Xperia 1 V just died

[Pucco_]

My Xperia 1 V just turned in to a black brick.

I just checked my mail and noted that battery was at 48%. 5 minutes later I should check an other thing and the phone was turned off. Now it is dead.

I have tried every suggestion I could find except prying the back panel open and disconnect the battery.

Vol+ and Power for 6 seconds, no response.

Vol+ and Power for 10 seconds and then power on, no response.

Vol+ and Power for 20 seconds and then power on, no response.

Vol+ and Power for 120 seconds and then power on, no response.

Holding Vol- and connect to PC with Xperia Companion trying to reset to factory, no response.

The phone does not charge. Measuring current when trying to charge shows 4 mA.

Is there anything else I could try.

[Pucco_]

An update. I used an hot air soldering equipment to soften the glue an took the back off. After a little disassembly I could unplug the battery connector. The battery voltage was 3.8V which is inline with the 48% I seen on the status bar. After reassembly it's still not working.