Every part must come from the same source to ensure they are versions of the same split archive.
While specific board firmware is usually found on tech forums, you can check the Sanyo Support Page for official general updates. 2. Extracting the Multi-Part Archive Download CV338H A42 1366x768 SANYO USB part04 rar
Plug in and power on the TV; many boards like the will detect the file and start the update automatically. Every part must come from the same source
Since you are looking for Part 4 specifically, you likely already have some parts. To avoid corruption, ensure: Extracting the Multi-Part Archive Plug in and power
Firmware for the CV338H-A42 board is often hosted on community forums or file-sharing sites like 4shared.
Copy the single extracted firmware file (not the .rar parts) to the root directory of the USB drive. Update TV: Power off the TV and unplug it. Insert the USB drive into the TV's USB port.