My LG 50PC3D was manuf in June 2006. Just today the screen is black and flickering 1 wide band of dimlit grey slightly off to the left. The indicator light stays solid green. Any idea what may be causing this. I have checked all connections. The sound seems to be working fine but there is no picture.

I would first check for swollen capacitors on the power supply board. This model has about 9 under rated capacitors that usually go bad. The original caps are 3300 uF rated at 10 Vdc., and they should be replaced with 3300 uF capacitors rated at 16 Volts DC, 105 degree types. A failure on this board could also affect the other boards in the set so correcting this problem may not remove the symptoms.