1/3 screen backlight off after mainboard replacement

[rvs2]

TV: UE46D6570

Mainboard replaced to BN94-05482L (from UE32D6510)

Problem: 1/3 top part of screen is like w/o backlight. It is clearly seen on video:
https://www.dropbox.com/s/p1hlnrzi91f6f ... .04.42.mp4

I have tried to select each of available panel types w/o success:

Code: Select all

46A2UF7E
46A2UF8E
46A1UF0E
46L1UF0E
461PUF0E
46L1UF3E
46P1UF3E
46L1UF6E
46A1UF6E
46P1UF6E
46A1UF7E - 3D
46A1UF4E - 3D

Strange is, that service menu is visible on full screen. I guess mainboard i have bought is not suitable for panel on my TV (panel code LTJ460HW02/J), but maybe here is some solution? Anyone?