TCL 55D1620 Manual page 18

Factory Test & Alignment Specification For MT56 Series (V1.0)
How to upgrade FLASH Software
1. USB Upgrade

Download the update file (generally named V8-MT56551-LF1VXXX.pkg) to the root directory of your
USB device, and make sure there's no other bin file named analogously. Then insert the USB device
to USB interface of TV set.

Power on the TV set, Press and hold on the menu key of key board at the same time. If the TV is
updating, you'll see the below screen:

Upgrade process takes about 3~5 minutes.

After updating, the TV set will reset automatically.
2. Online Upgrade
 Download the bin zip file "V8-MT56551-LF1VXXX.Zip" to the root directory of your USB device, and
do not change the file name. Then insert the USB device to USB interface of TV set.

Press RCU
Upgrade/Local Update . If the upgrade file is found, TV will give a message that it verifying. TV
displays a warning message, it means selecting "confirm" to continue or "cancel" to exit. During
updating, do not power off the TV set.

After updating, the TV set will reset automatically.
Menu/Settings/Picture/Contrast/1,9,5,0/Service
16
menu/USB Update /Main