: You can request a firmware update file directly from TCL's after-sales team.
The TV should detect the file and begin the upgrade automatically.
Navigate to > Device Preferences > About > System Update . Download TCL LED40S4900 Firmware part4 rar
Press and hold the on the TV (not the remote) for approximately 10 seconds.
Warning: Always verify the source to avoid malware or incompatible files that could brick your TV. : You can request a firmware update file
Select to check for and install the latest official software directly from TCL.
: Community forums or specialized repair sites (like Latinafy ) sometimes host these files to resolve "locked" startup issues. a network update is safer:
If your TV still powers on and can access the internet, a network update is safer: