iPhone 6s screen is black but is powered on
I've replaced the screen in an iPhone 6s and connected it all back up but all there is is a black screen. I know there is power in the phone as it vibrates and every time you turn the phone in the screen flashes and shows the lock screen then goes black again. Not sure what to do as I've tried different screen disconnecting the battery, tried only connecting the screen cable and can not seem to do a reset as it goes in to dfu mode but obviously can not get it out as phone is black. Help would be much appreciated.
Is this a good question?