Warning: Installing the wrong firmware version can "brick" your board permanently. Always verify your screen panel model before proceeding. Prepare a USB Drive: Use a thumb drive (1GB or larger) and format it to Download the Firmware:
Before touching a single file, you must understand the hardware architecture. Tp.mt5522.pc821 Firmware
Insert the drive into the USB port while the TV is unplugged. Warning: Installing the wrong firmware version can "brick"