ipad air 1st gen won't power on, thought it was the charging port but it reads 5V on the multimeter when plugged in....

"Update: As we all know aftermarket is having some issues with certain LCDs on IOS 11, however it is happening for some and some of you aren't experiencing any issues. This unfortunately has to do with the IC Driver Software that is in the LCD. Hancai and Tianma LCDs that use Copy Driver, Aichuangjia (Flex/IC Manufacturer) are not compatible. The use of the IC isn't strong enough to handle the iOS configuration which will cause the IC to shutdown and have no touch. Please Keep in mind that there is about 100s of different Flex/IC manufacturers so your LCD which is Tianma could be compatible and the other person having Tianma may not be. Generally it costs more for better Flex/IC which is the main core functionality. It's best to return to your supplier if you get any of those which don't work and know if it's compatible or not."