LG 50LN5750 has backlighty and sound and no image

[nickmatine]

hi there
i have a tv LG LG 50LN5750 has backlighty and sound and no image
there is any schematics or any idea what i can check?
thanks

[budm]

Re: LG 50LN5750 has backlighty and sound and no image

You can start by uploading good clear pictures of the whole backside of the TV so we can see all the boards and how they are connected together.

[nickmatine]

Re: LG 50LN5750 has backlighty and sound and no image

i have some pictures

[budm]

Re: LG 50LN5750 has backlighty and sound and no image

https://www.badcaps.net/forum/attach...4&d=1458593721

Check that white Fuse F1 on the T-CON board to see if you do have 12VDC at both ends with ref. to the chassis GND.

[nickmatine]

Re: LG 50LN5750 has backlighty and sound and no image

fuse is ok
but no 12v

[budm]

Re: LG 50LN5750 has backlighty and sound and no image

12V is from the main board fed through a switched power MOSFET.
So there should be the MOSFET close to the LVDS connector on the main board that you need to locate.
As you can see that 4 pins on the LVDS connectors are connected to the T-CON fuse, so you need to look at the other end of the LVDS on the main board side to see where those 4 pins are connected to.

[budm]

Re: LG 50LN5750 has backlighty and sound and no image

Is your main board LG EBT62387764? as printed on the orange barcode?
http://www.shopjimmy.com/lg-ebt62387...5ln5790-ui.htm

[nickmatine]

Re: LG 50LN5750 has backlighty and sound and no image

code is not the same but mainboard seems be the same
main is 37ebt000
and on site is 39ebt000
but what i see is the same

[budm]

Re: LG 50LN5750 has backlighty and sound and no image

You can disconnect the LVDS on the T-CON side and see if you will get the 12VDC on the 4 pins of the LVDS connector on the main board side when TV is turned on.

[nickmatine]

Re: LG 50LN5750 has backlighty and sound and no image

i do not have 12 v on any pin
tcon is not connected

[budm]

Re: LG 50LN5750 has backlighty and sound and no image

OK, the next step will be tracing the power pins on the LVDS connector to see where they go to next, it should ending up at the MOSFET's pin some where on the main board.