: The process can take 5–15 minutes. Do not power off or unplug the TV during this time, as it can permanently damage the mainboard.
Download the provided files. If they are in multiple parts, ensure you have every part before attempting extraction. Installation Guide (USB Method) Download RT2851V09 3840x2160 Kivi 55U730GU part08 rar
If the TV is stuck on a black screen or boot loop, the provides detailed power charts and voltage checks for components like the UP3D1 (3.3V) and U1D1 (1.0V) regulators. : The process can take 5–15 minutes