lenovo v580 only backlight on display

[s.m.hosein]

la58 mb is the part number
i have display on hdmi and crt port perfectly but on the laptop screen only have backlight and nothing else
led screen and lvds cable has been changed and still same problem
so anyone agree that the pch chip needs to be replaced????

[caspian]

Re: lenovo v580 only backlight on display

not exactly,
having display on external monitor means the PCH is probably OK.
test the screen on another laptop.

[s.m.hosein]

Re: lenovo v580 only backlight on display

as i said the led screen and lvds cable is replaced but still same problem
the pch manage hdmi lvds and crt but the part that manage the crt and hdmi is diffrent than lvds....
if i have not backlight on screen maybe the resistors behind the lvds socket was dead but the problem is lights on but no data signal on screen

[caspian]

Re: lenovo v580 only backlight on display

upload the schematics to check.

[santiago flores]

Re: lenovo v580 only backlight on display

si la pantalla led de 40 pines no ilumina pero se ve imagen a fondo, puede ser por muchos problemas, pero te diré la mas común, falta voltaje de 3v en los pines 5 y 6. empesando a contar del pin de 19v. espero que te sirva