iphone 5s only backlight no image

Hello 2 all and happy remaining hollidays. As the title says,i’m having some problems with an iphone 5s. It doesnt show any image,just the backlight works. The phone starts,i can use it,except there is no image on the screen. I have already tried with some originals lcds with no luck,so the problem is on the mainboard. I would appreciate a little help with what i can try to resolder,change or jump? Thanks