Default [Q] pc can't recognize and can't charge when switched on

Hi everybody
After updating my Xperia t, pc can't recognize it and charger works only when it is switched off. Also I can boot not to flash mode nor fastboot mode. The led turns green but after a few seconds it goes to charging and can't go to.flash. Charger and cable has no issue and works fine with another phones. The rom was official and I flashed with flash boot. Can I do something to solve it?
Thanks for your help