Z5 have charger connected sound but wont charge

I have Z5 dual.When I connect charger I have sound, sony logo on white acreen then battery screen but battery is not charging.I tried another battery, another chargers and all button combinations, nothing works.I opened phone and checked voltage on usb connector and it is fine, but when I measure voltage on battery board connector it is only 0.86 V so I gues that problem is on board.Anybody have some idea what could be the problem and what to check?