Sharp LC-39LE440M backlight okbut no picture and no sound how to repair

You need new LED backlight strips, a power/inverter board can cause this as well but on Sharp-Hisense sets it's been the backlights that are bad in most sets we repair in our service center.

If your able test the various power supply rails and see if they are ok

The tcon bard or the LCD panel is faulty. Can confirm by replacing the TCON board.
If you wish to get some details; check the site linked here. Pull up older posts....
http://electro-medical.blogspot.com/

lc-39le440m does have a usb media player ,if you able to view file in the drive ,but unable to play it file format might wrong , else the port/board is damaged

Sounds like a backlight either power to the backlight or the backlight itself. It's probably going to require a trip to a repair shop.

If you have sound but no picture, not even the menu, then you backlight controller may be faulty and will require repair or replacement.

Ur LCD backlight inverter board is dead.Replaced this board will get picture back.Tries Shopjimmy.com,Ebay.com to buy a refurbish LCD backlight inverter board,it a long board shape.

This is very common in sharp tvs.U turn it on.U get power on light stable right?U hear a click,one or twice,sometime tv is good right?Sometime POWER light and OPC light flashes?Push the power button on/off couples times will work, picture will come on.If keep trying off/on couples time after POWER and OPC flashes,don't ever stop and never get backlight and picture.Ur Video backlight board is dead must replaced.