My Sound Comes On But No Picture, I Heard You Can Update With Usb Flashdrive?

If you try to turn this set on in a very dark room and you see the panel light up slightly for a couple seconds then it goes dark then your problem will likely be an internal back light (inside the LCD panel, behind the glass LCD display). The price to replace the panel is too high, and not worth the cost. But in some cases the section of the inverter board that controls the florescent lamp (back light) that's not properly lighting, can be damaged giving the same symptom, or if the panel never lights up when first turned on. In this case, the inverter can be purchased separately and this is a much cheaper alternative. there are two inverter repair kits available dependent upon which panel you TV has. Taking the back off to see the tag on the back of the panel is needed to ensure you are getting the right one.

for the LCD AX080E002B

for the LCD AX080A030B

They are both in stock (note there is a core charge of either $40 or $42) from here: http://www.andrewselectronics.com/welcome.aspx

In the same dark room, if you put a bright flashlight against the panel carefully (easy to scratch) you will see the video is present, but because the back lights are not working.

If the panel lights up and stays lit, but there is no picture then the T-Con board (part of the panel and not available separately) or the LVDS cable that supplies the video to the panel from the "Main" board. Pull the LVDS cable and re-seat it to see if it's just a bad connection.