My screen doesnt turn on after diassembling and cleaning laptop

Hey there

I opened up my G512 LV to clean it up and change the silicons of it and add an extra ssd. After puting everything back together carefully and reassembled it the screen is not turning on … its dimmed and I can see something of windows by puting light on lcd.

Everything is fine with external display.

Every part of laptop ( battrey, ram, cpu Etc ) works fine.

But there is no luck with Built in display its just dimmed or better to say blacked out.

I also switched rams and reconnected the lcd cable to motherboard serveral times and no luck also tried hard reset and win + ctrl + shift + n.

I even tried electrisity discharge of mother board ( took off battrey and no adapter then holded power for 30sec ).