Samsung UN46EH5300FXZA LED smart tv will not power on. My little niece grabbed remote and a menu appeared on tv. Never seen it before. I saw an options then tv powered off. No power since.

What's the issue?

Samsung Smart TV hidden secret menu allows you to do a factory reset and also connect some Bluetooth devices which you were unable to do before. Be careful while fiddling with these options as I cannot take any guarantee if you spoil the TV settings. The Samsung Smart TV I used in the video is Samsung F4500. The secret menu will not open with a smart remote. You may buy or borrow the original normal rectangular Samsung remote to access the secret menu but I am not so sure that will work.
Here are all methods to access the secret menu of different Samsung smart TV:
Method 1

Put the TV on standby and then push in series these buttons on the remote: 'info, menu, mute, power' the TV will then turn itself on and display a menu.
Method 2

Turn the power off. On the remote, press Mute followed by 1, 8, 2, Power in sequence.
Method 3

With the TV in standby, press the {DISPLAY} {P.STD} {MUTE} {POWER} on the remote.
Method 4

With the TV in standby, press the {SLEEP} {P.STD} {MUTE} {POWER} on the remote.
Method 5

With the TV in standby, press the {DISPLAY} {MENU} {MUTE} {POWER} on the remote.
Method 6

With the TV on standby. On the remote, press Mute followed by 1, 1, 9, Enter in sequence.
Method 7 for Smart TV RU7100, NU7090 Series 7 (suggested by viewer Caleb Harch)

Most Samsung Smart TVs have a jog control (joystick) located underneath either in the middle, right or left side. When you find it, push and hold the center button to power on your TV. To power off your TV, push the center button, a pop-up menu appears.

Many Samsung TVs use a Jog control instead of buttons to control the TV without the remote. This control is located on the rear or bottom right side of the TV and will feel like a little joystick. 1. To power the TV on push in on the Jog.
https://www.samsung.com/za/support/tv-audio-video/how-do-i-power-on-and-off-my-samsung-tv-without-the-remote/

If the TV displays the menu or Smart Hub when you press the button on the remote - the TV is on, it's just displaying a black screen. Change the Source on the TV to another input. See the page on Samsung TV has No Picture for more troubleshooting steps.

Depending on the TV, there will be a Jog Controller or TV Control Stick that will allow you to access the TV menu and change the source. Use the control on the TV to select an option - toggle it left or right to see if anything appears on the TV.
If the control menu appears on the screen, the TV is on but not displaying any input. Check the connections or change the input source on the TV. If the controller button works on the TV, but not the remote, check the batteries in the remote control.

Unplug the TV from the power source and leave it for a minute or two. Reconnect the power cable directly to the wall rather than a surge protector. If the TV Standby light appears - the TV is receiving power. If the Standby light still doesn't appear, please get in touch to organise a service.

Hi There,
It appears to be a case of backlight failure. It is a common problem with LED TVs. Some of the LEDs in the backlight must have gone bad. It is repairable but needs an expert to do.

Look, enough is enough, bite the bullet and replace the TV, they are so cheap right now.

If you wish to get some details; check the site linked here. Pull up older posts.
http://electronicshelponline.blogspot.com/

Here is what to check when your TV is turned on, power light is ON, but no picture is seen or sound is heard:

1 - Be sure the component you are using (Xbox, Cable, SAT, ROKU) is turned ON.
2 - Check to be sure all cable and cords are securely connected to the TV inputs and component outputs.
3 - Make sure you are on the correct input as some TV's will show a black screen if there is nothing connected to that input.
4 - Unplug the input you are trying to use from the TV (such as an HDMI Cable) and plug it back in.
5 - Check for signs of damage on all cords and cables from the TV to all components.
6 - Make sure the TV is not in ENERGY SAVE MODE, press the button on the remote control to go back to normal mode.
7 - Unplug the TV for 10 minutes to see if there was a temporary one time issue with the TV.
8 - Disconnect the TV from power for 2 minutes, then when plugging it back in PRESS AND HOLD THE POWER BUTTON ON THE TV FOR 10 to 20 SECONDS to try and force the TV to reset.
9 - If after checking all these different issues, you may have a Faulty Power Supply Board, A Bad Capacitor on the Power Supply Board, Loose Wire Harness, or Loose Ribbon Connector in the TV itself.
10 - Most likely when a TV has the power light ON but NO PICTURE and NO SOUND, it is the Power Supply Board that has failed.

BTW, here are solutions for you to play iTunes movies on Samsung smart TV

On your Samsung remote. Press the MENU button. At the botttom of your screen you have the setup selections. Scroll over to the SOUND option and select that, A menu should appear and toward the bottom of the menu you should see MELODY. Scroll down to that and select ON or OFF...