LG 55LV9500 LED TV Black Screen

[talonesi]

I have a LG 55lv9500 TV. Once the TV powers on the screen remains black continuously (as if it never turns on). I can tell the TV powered on due to the status lights displaying on the front panel. Prior to failure the TV used to display the LG splash screen and the time first. It doesn't make it that far at this point.

I tried the flash light test, I was unable to see the menu or anything on the screen. I am unable to display content from any of the inputs. I don't have sound. Upon removing the back cover I do not see the led lights. It feels like the t-con, main board, or LEDs based on my limited 1 day of research. What are your thoughts to further isolate the issue?

[dick_barton]

Re: LG 55LV9500 LED TV Black Screen

Can you supply sharp focused pictures of your circuit boards.

[tvtimmy]

Re: LG 55LV9500 LED TV Black Screen

Take out the main board. Remove the 4 spring loaded hold down studs. Use a heat gun with the smallest nozzle it has. Turn it on LOW so you dont blow things off the board. Remove the slimy rubber heat sink thing on top of the cpu chip and heat the whole chip up for about 45 seconds. Let cool, put heatsinks back on, install board, and enjoy the now working tv.

[talonesi]

Re: LG 55LV9500 LED TV Black Screen

Thanks Dick.. please see the attached.

[talonesi]

Re: LG 55LV9500 LED TV Black Screen

@TVTimmy - just to confirm I'm remove the board in the final picture. The black rectangle is the heat sink with the 4 silver screws. Heat the cpu chip for 45, cool, and reattach? I'm intrigued.

[tvtimmy]

Re: LG 55LV9500 LED TV Black Screen

Yes. I have done this to 8 lg tvs,all came back to life. You can put some heatsink compound on the bga chip and the rubber heatsink to help cool it. Those studs have to be pinched on the bottom side and pulled out.

[talonesi]

Re: LG 55LV9500 LED TV Black Screen

Yes. I have done this to 8 lg tvs,all came back to life. You can put some heatsink compound on the bga chip and the rubber heatsink to help cool it. Those studs have to be pinched on the bottom side and pulled out.

TvTimmy: You can add a 9th to the list. I appears I'm back in business. Thanks so much for your help. Quick question - I didn't do a great job documenting the breakdown and screw schematics so I'm trying to piece the cover back together. The power cord is giving me trouble - it kinks or when positioned in another way bows the outside cover. I can't see to get it to lay correctly. Any advice?

[tvtimmy]

Re: LG 55LV9500 LED TV Black Screen

If I remember correctly, the cord fits into the cover plate and then a screw goes through. And holds everything together. The cord hole must line up, if not, rotate a 1/4 turn.
Send a pic if Im wrong.

[talonesi]

Re: LG 55LV9500 LED TV Black Screen

Thanks again, please see the attached. It is as if they didn't make the plastic coating short enough. If placed directly down it is about a 1/4" too long and the screw won't catch. I'm half tempted to put the bare cord thru the slot rather than the cord adapter.

[talonesi]

Re: LG 55LV9500 LED TV Black Screen

Additionally if you have any guidance on the screw replacements I'll take it. I have 4 different size screws remaining (not counting the power cord screw) 3 really small, 14 medium, 5 large, 2 xtra large. The large and extra large are the same gauge but different lengths. It appears the really small and medium are the same gauge but also different lengths. Meanwhile the hols looks the same.

[tvtimmy]

Re: LG 55LV9500 LED TV Black Screen

The square part of the cord goes in the molded slits in the cover. When it is correct the hole in the tab will line up with the cover and the mounting hole.

[talonesi]

Re: LG 55LV9500 LED TV Black Screen

Sorry if I being thick headed. Please see the attached. It is turned at 90 degree but as you can see the slot doesn't align to allow the screw hole on the tab to align to the cover screw hole. Am I thinking about this correctly?

[tvtimmy]

Re: LG 55LV9500 LED TV Black Screen

Filp the cover around. Try untill the hole lines up. Work all combinations of it, you will get it. By the way, the cord comes out of towards the bottom of the tv.