.Please make careful check of the flex cable, the contact pins even the LCD display(special the 4 corner around it) not get any damage, debris or block things? 2. Another important point is keep phone shut down till the install complicated. 3.Make sure the flex cable aligned up with logic board perfect and firmly?(Till the snap sound heard) 4.Sometimes battery may drained up,please kind connect the phone to AC charge5.Another important point is the wifi antenna screws, make it not quite just appropriate hold it, cause this maybe also some affect of the LCD connections. Hope above advice some help to you, and we will wait your latest news. 6.Finally you can put back with your origin one to have an contrast. .