Screen is dark but if i put flashlight on screen i can read it

If the TV's screen still remains dark unplug it and then also push the power button for about at least one minute and then plug it back in. See if that resets your TV. If it still is remaining dark use a flashlight and angle it against the screen with the TV at a station or a channel where you can hear the sound See if you can make out shadows and shapes on the screen. It could be that the screen has stopped working and needs to be replaced.

LG stands for Lousy Garbage.

Back-light inverter fault. Contact any service technician. If you wish to get some details, check the site linked here. Surf the site in "MOSAIC" view. It will make surf easy. Surf the site with patience.
http://electronicshelponline.blogspot.com/

Digital processor board is faulty. Contact any experienced service technician.

This sounds like the back-lights have quit working. This is made up with an inverter (ballast) and fluorescent lamps. I want you to try something. In a very dark room turn the tv on and watch what happens to the screen. There is three things that can happen. first the screen will stay completely black. This means the inverter never fired, and this is usually a failed inverter, but sometimes the power supply may fail. there is also a rare time the main module never outputted the signal to activate the inverter, but this is rare because you can hear the audio. So obviously the main is working at least 90%. The second thing that can happen is the screen will light for a split second then go black. This usually means that you have a bad lamp. These lamps are physically locate inside the LCD panel, and the replacement cost exceeds the price of a new unit. You may even see a dark area in the screen. The slight glow will not be uniformly lit through out the screen. Finally the last thing you may see is the screen has a slight glow. This means the back-lights work, but the video portion isn't showing. This usually means the driver board (T-con) has failed. This is probably not available separately, so you must replace the panel to fix it. And like before, the replacement cost exceeds the price of a new unit. One more thing to do when the set is on and in the very dark room if the screen is black, point a very intense flashlight into the screen. Put the flashlight against the lcd screen and see that you have video moving around the glow of the flashlight.

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.

It may be the internal backlight that is failing. When the display has failed but still has power, take a flashlight and hold it close to the screen, move the flashlight all around the screen and check if you can see anything. The display will be dark, but you should be able to make out the image that is there with the flashlight technique. If you can see an image on-screen, then your backlight has failed and you will need to replace the monitor. Weather or not you see an image is not a critical issue, but a tool to verify if the backlight is off or some other issue is causing the problem.
Note, it may be difficult to detect an image on the un-light display, for example if you have a dark image as your desktop background. So make sure to fully scan your display (top to bottom, and left to right covering the entire screen) with the flashlight technique in order to see any image on-screen.

It may be the internal backlight that is failing. You can take a flashlight and hold it close to the screen, move the flashlight all around the screen and check if you can see anything. The display will be dark, but you should be able to make out the image that is there with the flashlight technique. If you can see an image on-screen, then your backlight has failed and you will need to replace the monitor. Weather or not you see an image is not a critical issue, but a tool to verify if the backlight is off or some other issue is causing the problem.
Note, it may be difficult to detect an image on the un-light display, for example if you have a dark image as your desktop background. So make sure to fully scan your display (top to bottom, and left to right covering the entire screen) with the flashlight technique in order to see any image on-screen.

To adjust the contrast, turn the calculator on. Press and release the 2ND key. Press and hold the Up-arrow to increase or the Down-arrow to decrease the contrast.

nyounger4242, Very common problem!! learn to do flashlight test to evaluate "switch-mode-power-supply" status. Read my FIXYA profile to find out all you need to know about Black, or Black and Blank lcd screen fixes and the options you have. Your monitor NO DIFFERENT than any other CCFL Back-lit LCD monitor in it's basic design and operation!! Good luck with repair. Use warranty if possible. Read, Read, Read, before you do anything!!!! 12fixlouie