If lcd light is not working in Samsung Galaxy S4 I9505 then we will not be able to watch any text on display.light can be dim or may be blank.Samsung Galaxy S4 Display Light IC Solution Jumper Problem Ways can be solve in a few steps as given in this post.
Samsung Galaxy S4 I9505 Display Light Jumper
Samsung Galaxy S4 Lcd Light Not Working
Samsung I9505 Display Ic Solution, White Display,Display Blank,Display Light Jumper Ways
after dis assembling samsung galaxy s4 check mother board if there is any carbon water damage or rust.clean whole board with electronics cleaner and then apply hot air for a few mints so that it can be dry.
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