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.

This is what emma tells me
Xperia S JB 4.1.2 (build 6.2.B.1.96)

I have been searching for a stock rom, but can't find it.
Do you have a link ?

Thank you, thought that was a custom firmware beceause of the name.

I get the following error when I try to flash it

29/012/2014 22:12:15 - INFO - <- This level is successfully initialized
29/012/2014 22:12:15 - INFO - Flashtool Version 0.9.10.1 built on 2013-01-09 19:49:47
29/012/2014 22:12:15 - INFO - You can drag and drop ftf files here to start flashing them
29/012/2014 22:12:21 - INFO - Device connected in flash mode
29/012/2014 22:12:22 - INFO - Selected LT26i_1252-0023_6.2.B.1.96_GENERIC-user_CUST_1257-6921_R3H.ftf
29/012/2014 22:12:22 - INFO - Preparing files for flashing
29/012/2014 22:12:41 - INFO - Please connect your device into flashmode.
29/012/2014 22:12:42 - INFO - Opening device for R/W
29/012/2014 22:12:43 - INFO - Reading device information
29/012/2014 22:12:58 - INFO - Unable to read from phone after having opened it.
29/012/2014 22:12:58 - INFO - trying to continue anyway
29/012/2014 22:12:58 - INFO - Start Flashing
29/012/2014 22:12:58 - INFO - Processing loader
29/012/2014 22:12:58 - INFO - Checking header
29/012/2014 22:12:58 - INFO - Ending flash session
29/012/2014 22:12:58 - ERROR - Error in processHeader : 2
29/012/2014 22:12:58 - ERROR - Error flashing. Aborted
29/012/2014 22:12:58 - INFO - Device disconnected

I can flash this one, but without any change.
When I push the power button the green led flashes just once.
But the enclosure where the cpu is located is getting a little warm, so I think it is doing something.

The flash ended successful so I don't think there is anything wrong with the drivers but the problem still stays.
when I push the powerbutton only the green led flashes one time nothing else.
But I think it's doing something, beceause the cpu is getting warm.

Is there a hardware diagnose tool for windows ?

TeChNoMiC said:

plz connect in falshmod, then look windows device manager.
is there a yellow !

and you install the driver?

Click to expand...

Click to collapse

just tried it, there is no yellow !
When I connect the phone it says semc flash deveice in the deveice manager