Running BN44-00428B Power Supply Without Motherboard on UE55D7090LS Smart TV

Hello.
Problem with tv as in the subject.
Tv turns on, you can see the logo smart tv and reset (the relay is ticking) and so in the circle. The backlight works during this time.
After disconnecting the motherboard there is no reaction (no backlight). So far, in Samsung, always after disconnecting the motherboard, the backlight was activated, which meant that the power supply and the backlight is working (at least I always had it).

BN44-00428B power supply
The question I have is how to run this power supply without a motherboard.
Voltage on CNM801
pin 18 - stb 5.3V
pin 20 - PS-ON 3.3V

I mean just how to run the power supply and to check the backlight. (for now I do not want to disassemble the matrix).

The power supply I would give up, and thought about the backlight, it's the disease of this model.

That's what I wrote about it.
I will answer for myself.
The power supply starts the backlight without the motherboard connected.

My fault was in the backlight.

Fault:
Smart TV logo and reset (tick relay) and so on in the circle.
The backlight was but with a closer look the lower part of the picture was darker.

Diagnosis:
In my case damaged LED backlight (side lighting left and right side).
Break in the led circuit. The picture shows diodes that did not shine.


Break in the last led.
I close the topic.