Turn the TV on while pressing and holding the Standby/Power button on the remote or TV until the "Software Updating" message appears.
Go to the Hisense Firmware Download portal and enter your TV's Serial Number to get the correct version for your specific panel. Turn the TV on while pressing and holding
If the website does not list your model, contact Hisense Support directly. They can provide a direct download link or mail a USB drive with the correct firmware. How to Install via USB Turn the TV on while pressing and holding
Place the upgrade_loader.pkg (or similar) file into the root directory of the USB. Turn the TV on while pressing and holding