@epkrichi sounds like you have a lot going on here with your PCB. It’ll be a bit complicated since there are multiple things that are not quite as they should. Since there is some repair information available but not as much as we would like to, I’d try a new display assembly as a starting point. Anyhow here is what I do have which is the troubleshooting section and the schematics for your model. Hope this helps getting you started. [document|25672][document|25671]
Of course you could always try and install jumpers like these
[image|2436752]
and see if your backlight comes back on :-)