Copy the downloaded firmware file (often named Update.img or a .zip file) directly to the root directory of your USB drive—do not put it inside any folders. Insert and Flash: Power off your TCL TV. Insert the USB drive into the TV's USB port.
Keep holding the button for roughly until an automated upgrade progress bar appears on screen. Release the button and let the system finish processing. Recommended Alternatives A2zrom.com Tcl Tv