Default Xperia S /lt26i black screen no boot

I hope you guys can help me revive my xperia S.
I have a strange problem with my phone and can't seem te fix it myself.
I can't boot my phone anymore.
I can get it into flash (green led) and fastboot mode (blue led) and can flash it, but without success.

If I connect my phone to the charger I only get a red led but it doesn't seem to charge.
The phone is recognized in windows and I can lock and unlock my bootloader and see the phone information.
but when I push the power button the only thing that happens is a green led for a second but nothing else.