t's possible that the 5-year-old accidentally changed the input source on the Samsung TV, which is why you can't get the Fire Stick to work. Here are the steps you can follow to switch the input source back to the HDMI port where your Fire Stick is connected:
Turn on your Samsung TV and your Amazon Fire Stick.
Using your Samsung remote, press the "Input" button.
A list of input sources should appear on your screen. Use the arrow keys on your remote to select the HDMI port where your Fire Stick is connected. The HDMI port may be labeled as "HDMI 1," "HDMI 2," or something similar.
Press the "Enter" or "OK" button on your remote to select the HDMI input source.
Your TV should now switch to the HDMI input where your Fire Stick is connected, and you should see the Fire Stick's home screen on your TV.
If you're still having trouble, try unplugging the Fire Stick and plugging it back in to make sure it's properly connected. Also, make sure the TV and Fire Stick are both updated to their latest software versions.
You have a bad COF IC on one of the panel boards, this is shutting down the power supply from over current, bad news is the set isn't repairable, you would need a new panel to fix the set, you won't find one anywhere.
You will need to unplug your TV from the power outlet and any power source for about 1 minute,then plug it back in. Check to see if the HDMI cable is properly connected.Or change it to a different socket. Do a factory reset.
Samsunghttps://www.samsung.com > ... > TV & AV
Apr 13, 2023 - Troubleshooting. 1 Check whether the lines on the screen are moving or permanent. 2 If the lines sway, check the input source (HDMI 1, Video, ...
Have you tested the backlights by removing the connector going to the main from power board, this will tell if the hot side of the power board is working and you will get backlights if they work?
This sound like an issue with the x-main board, if you unhook the power cable going from the power supply to the y-main board and you get VA and VS voltages there is about a 95% chance of the power board working ok, both the x and y main boards in this model set gave issues, one problem is going to be finding a board at a decent price, you can troubleshoot the board yourself, it's generally the mos-fet's that short, the ones that are attached to the heat sink. If you find some bad, replacement parts can be obtained from Mouser for a few bucks, they're easy to change with a soldering iron and some solder wick or sucker