G502 roblem

Hey,
i just received G502 with some hardware errors, just listen:

1. Phone turns on and shows SE logo, after that screen and keyboard lights go off..
2. I wait about 1 minute and phone boots and Locks keyboard.
3. If i press any button i see LCD is showing me everything but just on low lights, dimmed screen..
4. If i press * and Unlock, then lights go ON to i think 100% and keyboard lightning just flicker for about 1 second and then LCD and Keyboard Lights go off again, so i have to wait until phone keypad locks again.


What i want si to ask, what file i have to edit, screen drivers or something, to set DEFAULT lightning value to 50% or less?

or i have to PATCH my MAIN file to get lightning smaller?

or maybe someone know what is wrong on this phone? it is Keyboard? it is LCD? what can it be?