Chosen Solution
I have a 2019 KD65x750f with relaxing sound and backlight but no SONY splash screen or any menus. I plugged in a bootable USB stick with the latest firmware as it was named, nothing happened. I changed the name of to update_loader.pkg and I still am not hopeful anything is going to come of it. It is up and running in my garage as it is (backlight and music) so I am unsure if the USB stick is really doing anything at this point, I’ve left it for hours before, it doesn’t seem to do the firmware update. It has a new power board, a new main and a new T-con, before it was completely dead. Now I get a backlight and music but noting else so the TV is pretty much still useless. I will be grateful to anyone that can give me any input as to what to do next, I’m out of ideas. UPDATE 06/24/2021
Strange that I see this after I pull the USB stick There is really no data in those folders.
Are you saying that those folders got added after you plugged it into the TV? The Android icon is indicating something is in that folder. The LOST.DIR folder is empty per the icon. Since it was dead b4 you replaced board and is now doing something, it may be that a connector or 2 is not properly inserted. I would carefully recheck all connectors. There is also a possibility that one of the replacement boards is bad. If you replaced them all at once, I would reinstall one old one at a time to see if you can determine which one was originally bad. You might find one of the new ones bad doing this.
