screen in blank after LCD/Digitizer Replacement

I have an LG Lucid VS840 with a cracked screen. The phone still worked and I believe the LCD was intact. I bought a replacement digitizer/glass assembly and followed the video posted here on ifixit. When I put everything back together the phone turned on just fine however the screen remains blank. I can hear text messages come in and all sorts of the notification sounds but no screen. I figured it must be the LCD. I bought a replacement LCD and put everything back together and still have the same problem. I've checked all the connections and everything seems right. I have no idea what to do. Any suggestions?