My LG 55 inch smart tv has no picture. I can see the picture with a flashlight. And the voltage seems good on the LED. What might be the problem?

SOURCE: We just got a 55 inch LG LED TV. How do we set it

Easiset way is to use the HDMI Connecters and ports from the Direct TV box to the HDMI port on the TV...then set the imput source to the HDMI port that you used on the back of the TV.

SOURCE: I have a LG 55" smart TV and can not get the sound

get into your setting on your tv (menu) and click on the audio and make sure the speakers are in off position.

SOURCE: Tartan Pattern on screen of 55 inch samsung led tv

Suspect main board that processes all signal in and to the screen.

If not tried do see if same problem when rear inputs for audio/video are used.

Testimonial: "Appreciate your assistance and advice. Im sure Mrs E would love to use it as an excuse for a bigger TV (it will hide the power point that just happens to be visible behind the existing one...lol ;-))"

SOURCE: Samsung 55 inch Smart TV

It sounds that a capacitor inside the circuit of the has failed. It might have bursted. Check the power supply regulator board for the trouble. Normally electrolytic capacitors at this section should be suspected.

SOURCE: how do I replace SMART TV SCREEN MODEL NO : LG 55LM7600 55'' 3D 1080p Full HD LED LCD Smart TV

You cannot replace a screen that big. The manufacturers wont ship it to you. IT has to be done by an authorized service center.