Why wont my TV screen turn on

Derpzilla_9000 you have not told us if you have any kind of sound. Anyhow, first lets check your backlight. You need to verify that you have no image on all inputs. If it remains dark, unplug it and push the power button for about one minute, then plug it back in. See if that resets your TV.

If it remains dark, use a flashlight and angle it against the screen with the TV at a channel where you can hear the sound (you did not tell us if you do have audio :-) See if you can make out shadows or shapes. If you do, then it is your backlight that has failed. If you do not see anything, unplug your set and remove the back cover. Then visually check the boards for any obvious damage like domed or leaking capacitors. Check all the wiring and unplug the wires and plug them back in to make sure they are properly seated. Post some images of all of your boards with your question. Use this guide 기존 질문에 이미지 추가하기 for that, so we can see what you see.

Now unplug your set again (from the power board). Unplug the cable coming from the main board to the power board. Plug the power cord back in. that should turn your back lights on. You can see your backlights through the holes in the metal back panel of the display. Are they on? Good. Backlights are working. If not, good too. You now know that either your back lights have failed or your power board is not supplying the voltage to them. If no change, unplug your set. Reconnect the main board. Then you will need a multimeter to check the voltages on the connector from the main board cable. For that, we will need to see your boards so we can guide you a bit better. Hope that up to now, this all makes sense. ******