- unplug the power cord
- copy the file SISEU23X8M.bin on an empty usb stick fat32 formatted
- insert the usb stick in the tv and reconnect the power cord
- look at the standby led... at the beginning it flashes slowly, after about 1 minute it doubles the speed: update completed
- unplug the power cord and the usb stick and wait until the standby led turns off
- reconnect the power cord and turn on the tv: it will restart in first installation mode
if it doesn't work with the usb recovery, rewrite the spiflash U5 using the file SISEU23X8M.bin
here is the software (V20.0167) for GRANDIN LD39C25 LED39TC1700E