I have a Sharp TV (model LC-58Q7330U) that will not start up. Just shows the Roku logo for a few seconds and then turns off, shows the logo a few seconds, turns off in an endless loop. I wanted to try to recovery it by using a USB drive with a firmware image. I'm unable to acquire this as I don't know the Roku Model Number and since the TV is in a boot loop I can't access any menus to see it.
I do have both the TV serial number and a serial number from the Roku portal if needed, but I apparently need the Roku Model Number to get the firmware.
I'm currently having this issue with my 58 inch Sharp Roku tv. Tv worked great up until 2/6/21. Turned the tv on that day and it'll go to the Sharp-Roku TV logo in white display page, disappear to a black screen then continue flashing the Sharp-Roku TV logo in white logo then back to black screen continuously. I don't know if this was an update issue or what but Roku support is virtually no help at all. If anyone knows a solution for this, post it please. I have a 58 inch paperweight on my hands that I'm ready to throw out the window.
I call it collusion tactics. Nobody's responsible for anything. It's the constant theme. (The person's thread you replied to had to divine the Roku model number from thin air. There's no cross reference -- even though customers repeatedly demonstrate a need for it. That's how obfuscated the boundaries are. There's different model numbers depending on who you talk to.).
If I were you, I'd try the pinhole factory reset on the back of the tv. Unplug, press the power button for a minute to drain any capacitive energy. Then hold the pinhole reset button while plugging the tv in. Continue holding it 15-20 seconds until the front light flashes or dims (? This is a little unclear to me how the different brands might work). If you end up in the setup screen, you can tell it you'll connect to internet later. See if the problem exists when watching antenna tv or streaming through HDMI port.
Another thing you could try is the so-called cache clean:
Hit HOME 5 times. UP once. REWIND twice. FAST FORWARD twice. (Clears cache & tv reboots itself. Be patient. It takes 2-3 minutes for the tv to go black, and come back on)
If the tv is recognizing the remote (long enough to press those keys), it might fix it. It fixes some problems that factory reset doesn't.
These tvs have a modular board assembly. You can find videos about how to replace boards to fix different problems. That might be your only option if the above doesn't work.
"People are often amazed at how much we’ve done with the number of engineers we’ve got." (Roku CEO Anthony Wood, Austin Statesman, Oct 4, 2019). "Amazed" is one way of putting it.