Are you doing this to or just to upgrade ?
If the TV is totally dead, I can suggest alternative flashing methods. How to Update TCL Tv by USB Download TCL L40D2900 Software rar
Downloading and installing firmware for the TCL L40D2900 (often using the mainboard TP.MS1306.PB775) is typically done via a USB update, as this model may not receive over-the-air updates. 1. Preparation Confirm your TV uses the TP.MS1306.PB775 board, as firmwares are specific to this. Are you doing this to or just to upgrade
Use a USB drive (2GB–16GB recommended) formatted strictly to FAT32 . Keep holding the button until the screen shows
Keep holding the button until the screen shows a "Software Updating" message or the standby light flashes quickly. You can now release the button.
If the downloaded file is a .rar file, you must unpack it using software like WinRAR on a computer to obtain the .bin firmware file.
Copy the .bin or .zip file directly to the root directory of the USB drive (not inside a folder). Turn off your TCL L40D2900 and remove the power cable from the wall. Insert USB: Plug the USB drive into the USB port on the TV.
