Black LCD screen on MacBook Pro A1286 Late 2008

Hi all,

I tried all possible solutions but nothing worked for me so I try it this way. I would really appreciate any advice.

I got a Macbook Pro A1286 Late 2008 with broken screen. Everything else was working, so I bought a new LCD. After the replacement the LCD stays extremely dark but it is working (I checked it with flashlight trick). An external display is also working. I changed the LCD cable, tried resetting SMC, PRAM and so on. The seller of the LCD said, that the backlight inverter might be broken but as far as I know A1286 doesn’t have any inverter.

Do you have any other ideas what the problem might be?

Many thanks in advance!