Flashing firmware from unofficial sources (like multi-part RAR files from third-party forums) carries a high risk of permanently "bricking" your TV if the file is corrupted or for the wrong version of your hardware.
Most Sansui Android TVs can be updated directly from the menu. Navigate to Settings > Device Preferences > About > System Update to check for and install available updates. Download SANSUI CONTVSNX50FH18XAF part03 rar
If you are looking for a RAR file because your TV is stuck on a loading screen or "boot looping," try these steps before manually flashing firmware: If you are looking for a RAR file
You can visit the official Sansui Download page to search for firmware and manuals specifically for your model. Troubleshooting Boot Issues stuck on logo
Could you tell me the you're having with your TV (e.g., stuck on logo, black screen) so I can help you find the right fix?
Unplug the TV from the power outlet for at least 5 minutes, then plug it back in.