Chosen Solution

The LG 65UF6800 tv goes on and the menu and sound work fine, but the actual picture on the screen on any input is all snowy.

@fivestar9211 @roy_r if you checked all the inputs with different source and if your menu is clear but your screen is snowy, you are having problems with the main board.

I would suggest that the main board is your problem. As this unit is very warm during use and cools when shut down.The solder will expand and contract. This will produce poor grounds on all the HDMI connections, HDMI M1, HDMI 2, HDMI 3 and so on.One thing to try before you make a new board purchase try this. LVDS cables……….there should be two of these. Making for four connections. They are ribbon cables from power supply to main board. Carefully lift up the plastic connections, pull ribbon out and clean the connection with a clean pencil eraser. Ribbon and board connection, replace ribbon on each account. Thank you for asking, Matt of Martins TV Repair.

Try these options it should work for you. Turn off the digital noise reduction feature on the television. Turn off auto motion . Try changing picture modes, also see picture\color settings and turn off adaptive lighting from the settings . and other possible reason could be wrong settings, electrical distortion or glare on the screen.

Bad grounds on any video cable will cause this. You may have a problem with the cable / satellite box. You may have video connections crossed. Just trouble shooting. Check cables……I do believe that is a good place to start. Matt of Martins TV Repair. Update (11/24/2020) HDMI grounds on the board are possibly cracked. There is a tremendous amount of heat on these. As they cool they contract, when hot they expand, leaving bad grounds down the road. I have heard putting the board on a piece of cardboard into a preheated oven at per se 400 degrees for ten minutes then take out and cool for a couple hours. You will have to babysit and not burn this. Thanks for asking, Matt Of Martins TV Repair.

We are sure the main board is bad, we replaced many of those but now those board s are not chip, it must be a way to fix those, any suggestion ? we already tried reheat the main processor but still the same. Update (11/24/2020) replace the main board for sure will fix it. but we did not have time to pinpoint the issue with main board itself, I am sure is fixable

The video you’re playing is it on HDMI?