Screen is black. Replaced with new old screen, still broken

I was changing the hinges on my original screen which went black and wont not turn on. I figured the backlight had gone bad as i had been having some previous issues with the lvds cable showing weird colors. I decided to replace the screen with a new used screen from ebay that is 100 percent certified by the seller as having been working. I did the install and Im still having the same issue. You can see the screen if you used a flashlight but otherwise its black. What could be the problem?