Won't wake after sleep. back light comes on only

I replaced the digitizer and the LCD. it works great….but

when it sleeps. you can’t wake it other than turning on the backlight. Able to sleep+home to restart ipad.

after pressing sleep or auto sleep, you can still hear siri and sleep/cover clicks.

I understand that the mini 4,5 have a sleep/wake switch. am i wrong in thinking the mini 2 does not?