Chosen Solution
My Samsung un55fh6200fxza won’t properly boot up. It comes on, shows the logo for a second or two, then reboots. The red light on the front blinks 5 times, then repeats. When I take off the back and plug it in, the backlight comes on. I visually inspected the capacitors and don’t see anything out of the ordinary. Any ideas what I should check next? I’m not super technical, so the more simple the explanation, the better chance I’ll understand it. ;) Thanks! Update to add images
To close this out - I replaced the main board and everything works great! Thanks for the help, everyone!
@cschaaf Samsung does not officially support blink codes, so that won’t help us. I am a little stumped by this “When I take off the back and plug it in, the backlight comes on. “ Usually on Samsungs you can force the backlight on by disconnecting the cable from the power board to the main board. Since your backlight does come on it is most likely your main board that is not sending the signal or a failed t-con board. It is the power board the supplies power to the main board and it is the main board that turns everything on (very simplified). I suggest that you check the connectors on your power board with a multimeter against the values printed on the board. Let us know what values you get. Do not forget to check the T-con board (follow the flat ribbon cable coming of the main board. It should be going to the t-con board) and make sure it has power going to it. You can measure that on the fuse of that board. You should get around 12V DC on it.
