L310 что может быть

[milicis]

Yes, Try to put another working lcd, it helped to me, and be very carefull with pushing flex in connector, push it very straight inside otherwise flex is getting damaged. Check it under microscope also.
Maybe try to flash your phone too.

Is there welcome screen sound when turning on phone ?

[Horunshij]

Yes, Try to put another working lcd, it helped to me, and be very carefull with pushing flex in connector, push it very straight inside otherwise flex is getting damaged. Check it under microscope also.
Maybe try to flash your phone too.

Is there welcome screen sound when turning on phone ?

когда запускаю звук есть и подсветка-наверное всё таки диплей. Буду разбираться