We may get lucky and oldturkey03 has the service manual to help you out in doing that. If you are confident then you may like to try taking the old board out and putting in a new one. Unfortunately it's not always that simple.If you have sound when you play dvd or select TV mode then the likely culprit is a part on the picture board. The picture board on some TV's have capacitors that are prone to going bad.just replaced them on a cheap st £1.79. Most modern TV's have a power board, sound board and for want of a better term a picture board.
It's not likely that you need to replace the LCD unless you have dropped it or have obvious signs of damage to it, it is more likely that the power supply to the LCD is the problem.
