Sony Xperia Z3 Display Light Solution Jumper Ways
https://gsmfixer.blogspot.com/2015/10/sony-xperia-z3-display-light-solution.html
Sony Xperia Z3 Display Light problem is due to the LED placed on the back side of the LCD. When these LED lights are not working then there is no lighting on the screen. The manual solutions are to remove the battery and memory card and re-insert them. The hardware solution is given in the diagram pictures given below. Trace the points on the motherboard and make jumpers as shown.
