PROBLEM/MODEL:
ST18i XPERIA RAY NO LIGHTS/NO DISPLAY
SOLUTION:
JUST FOLLOW THIS PICTURE :tgy

Sony Xperia ST18i display and display light ways
1. try the five-point jumper to his lcd pin (see picture below)
if the lcd is still as before rehot or replace third emi filter lcd

2. if its lcd light not work after the fifth point jumper pin
lcd ..... replace the L7600 and V7601
open its schematic diagram