K52N screen

I have a Asus K52N, but it broke when it fell of the table.
Now when I start up the computer I get a quite normal picture of AMD logo (seems ok by its brightness), after that it goes black, but it once gave me a text in very low brightness.
Plugging in and external monitor seems to work fine.
What could be causing this problem?
Is it the power inverter board, LCD or GPU?
I think it is the inverter board, had another asus once and had a similar problem, I soldered a small wire to the coil thing since it looked loose and then it seemed to work.
But the fact that it works on first seconds makes me think that the problem could be deeper.

 

The K52N has a LED backlit screen, so there is no inverter. It is probably the screen itself that is broken or the connector has come loose.

 

Yes, but what is this then?
ASUS K52F LCD Inverter Board AS023215106 04G554012110 | eBay
It is for a different model, but the board is the same.
I checked with voltmeter and saw that 12V, 5V goes inside, but nothing comes out from the end, where 2 cables plug in.
Also nothing flows in that coil.

 

Ah OK, I don't know that model, just looked it up and it said LED screen in the specs.

 

i think i would try to reconnect the cable and see if that does the trick. It should be a quick fix as well.