TCL 49S403 User Manual page 131

12- and 6-digit codes
The USB update process uses a pair of codes to validate that you are authorized to
install an update, and to ensure you are not attempting to install an old, unsupported
version of the system software.
8. Using the TV remote control, select Next to move to the next screen, and then
use the on-screen keyboard to enter the 6-digit code. When finished, select OK.
The system update begins. Do not remove the USB flash drive until the TV
restarts.
When the update finishes, the TV restarts. You can check the new version number by
navigating to Settings > System > About.
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