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Plasma 50 inch LG TV bottom half screen black.

@sonu12 usually caused by a failed X-board. Check all the lines from the power supply to the X-board. Check your power board for any domed, leaking or otherwise damaged components. Pay particular attention to your caps. Post some images of what your screen displays as well as of all of your boards. For that you will have to remove the back from your set of course. Do not touch anything on the inside yet. Use this guide Adding images to an existing question for that. You will also have to give us your TV’s complete model number so we can try to help you further.