Backlight Screen not working on 2013 MacBook Air

Hi. I found a Macbook Air in the garbage that seemed quite broken. I wasn't really expecting it to work, but when I got home I plugged it in, booted it and it started up normally. I changed the admin password so I could log in and literally everything on the computer works fine with the exception of the screen. It seems as though the backlight is either burnt out or there's a cable detached somewhere. For background information, I have no idea what happened to this macbook. It seems like it was most likely dropped at some point as the bottom panel is unscrewed and has a big dent in it. I can't see any visible damage to the LCD though, and like I said the screen still works, but is 100% dim. I appreciate any input.