Generally all LCD TVs will have a T-Con (timing control board). What you describe here is exactly what you need. In some cases the T-con board is imbedded onto the screen (panel). The old term of picture tube is now called the panel. If this is the case, your TV cannot be repaired, as a new panel would be the price of a new TV. As a servicer, we are asked not to replace the panel. Thanks for asking. Matt of Martins TV Repair.
IN SOME CASES THE PROBELM CAN BE AN EEPROM IN THE SIGNAL BOARD. THE VIDEO WILL FREEZ WITH A TV LOGO OR MENU. ONCE AGAIN, NEED A BRAND, MODEL NUMBER AND YEAR OF MANUFACTURE. I MAY BE ABLE TO PIN POINT THE PROBLEM. MATT OF MARTINS TV REPAIR.