Turn the TV on while pressing and holding the Standby/Power button on the remote or TV until the "Software Updating" message appears.
The specific file you mentioned, "part2.rar," indicates a multi-part archive often found on unofficial firmware repositories. To ensure the safety and compatibility of your TV, it is strongly recommended to use official sources: Turn the TV on while pressing and holding
To download the firmware for the (Mainboard MS6586T 751 Turn the TV on while pressing and holding
For further assistance, you can also check community resources like the Hisense Reddit archive for alternative firmware versions. Turn the TV on while pressing and holding
Do not turn off the power until the TV automatically restarts.
Place the upgrade_loader.pkg (or similar) file into the root directory of the USB.