This is most likely a board level issue at this point if you have tried disconnecting and reconnecting the LCD. Sometimes the LCD backlight itself will be the problem but usually this case arises from board damage caused during repair. Usually a filter or resistor knocked off the board. Try the common troubleshooting steps first, such as resetting the ipad and checking all connections, and maybe try a replacement LCD if you have a shop near you that can help. Other than that, it will most likely be board level and a trip to the apple store for replacement. Another option, which I have not personally tried, is to contact the people at http://www.cyberdocllc.com/ for help. They do a lot of board level repair work and can help you out, and will always be cheaper than the apple store. Honestly, the only time that it is worth visiting the Apple store is if you are at a mall and waiting on your wife to finish shopping, it's a good way to kill a few hours. Other than that, buy online or repair locally!