If the screen suddenly goes blank, you can try to press and hold the power button at the top 10 seconds or so to see if the screen responds. You can also try to press and hold the home button and the power button for more than ten seconds to force a restart. This method can solve the problem of mild crash. If all the above steps fail, you can charge the ipad with your own power supply, and at the same time press the Home return button and the power lock button on the home screen. If the ipad still doesn't respond, it may be a hardware failure and needs to be tested in the after-sales service shop.