Why does my ipad not work after digitizer,LCD and battery replacement?

I recently replaced a iPad mini 2 digitizer and I accidently broke the LCD, so I ordered one and replaced it. It works, but when I turned it on it blinked the apple logo for a second and then it would just be a black, dim light and didn’t do anything else. When plugging it in to iTunes, it did not show up, but while windows was setting up the device, it said The iPad was in some sort of recovery mode. I don’t know what o do. I have replaced the battery and nothing, Help?