I have an HP Pavilion DV7-6B55DX that has an LED screen that started to flicker over time and finally went black. When you held a flashlight up to it you could see the Windows screen so first thought is an inverter but after taking the screen apart I realized it was an LED screen that did not have an inverter so my thought of replacing the inverter turned into ordering a replacement LED screen. I had also tested the laptop screen by hooking up an external monitor and that worked just great. I ordered a new LED screen and just received it today and installed it. No luck, still the same problem so not the LED screen.
I then took the laptop completely apart all the way down to the motherboard and checked all cables and connections. Reseated all connections and inspected the motherboard for any signs of damage but nothing. Read somewhere that the motherboard has a builtin fuse on the motherboard that can short out and if it is replaced or repaired with a little soldering it might work. Saw no signs of damage on the motherboard so reinatalled everything and fired it up to again the same issue.
It seems like a backlight issue but the LED screen has the backlight built in to my understanding so looking for insight and input from someone that has solved a similar problem with a laptop LED screen.