Public archives have cataloged specific dump files for this model and its chassis (TP.MS1306.PB775):
Because TCL’s website does not always provide public download links for these specific bin files, it is recommended to contact the TCL after-sales team if the community files do not work. They can often provide a direct link to the correct software based on your serial number. Download FLASH DUMP TCL L40D2900 rar
(2.3 MB) — Firmware specifically matched to the TP.MS1306.PB775 board. Public archives have cataloged specific dump files for
While holding the button, plug the TV back in or power it on. Continue holding for about until the upgrade screen appears. The process takes approximately 4 minutes to complete. Official Support Channels Download FLASH DUMP TCL L40D2900 rar