Fault to the main power supply regulator board. Check and replace damaged component/s at its main power regulator [SMPS] section circuit. Contact any service technician. If you wish to get some details; check the site linked here. Surf the site with patience. Pull up older posts.
http://electronicshelponline.blogspot.com/It will be best to replace the power supply regulator board as card basis rather than making "Surgery" to it; which usually will make loss for both money and time. Even though you can make it right, it will cost around an amount equal to the cost of a new board; including the cost of (spare parts + service charge) More to say, most of the spare parts to it will be difficult to get from open electronic spare part market. This is true to most of the flat panel TV power supply boards; irrespective of its brand and screen size.
Your TV need a through checkup. Main board, power supply regulator board, back-light inverter board need to be troubleshooted. Contact any service technician, or the authorized service center.
If you wish to get some details; check the site linked here. Pull up older posts. Surf the site with patience. http://electronicshelponline.blogspot.com/
The t con board or the LCD panels is faulty. Can confirm only by replacing the Tcon board.
If you wish to know more about Tcon board problems and troubleshooting then check the following link.
http://electro-medical.blogspot.com/
Please check the flat cable connections between TCON board and the LCD panel. If this is ok, then it is either the TCON board or the LCD panel itself. Good luck.
Check and replace the backlight inverter board. Do not think that it works only with some capacitors. The inverter transformers are the main component on that board, and always gets shorted inside, and is irrepariable.