Samsung led TV model UN40H6203AF no picture no sound no backlights. Flashlight test shows letters on screen after pressing menu button. Standby light blinks 5 times after turning on.

Is there any picture on the screen....does the menu show?

That is the right amount of voltage the issue is when one or more of the individual LED lights fail, the current changes and the power supply senses it and shuts down.

Lamps in the panel are bad...DON'T order the power supply like someone says on about every post he answers before testing the LED lamps or you will waist a lot of money.

The Audio and Video are two separate components and operate independently of each other. Therefore: The Video portion requires technical repair by a technician with the proper test equipment.

Hi Terry,

If you can see the faint picture in flash light means the power supply and the main board is working. The real culprit is the backlight. Even one bad LED in the backlight will switch off the whole array. To repair this fault the panel has to be opened and the defective LED or LEDs are to be replaced.

This is a complicated, delicate and risky job and must be attempted by an expert only. You may end up damaging the screen permanently if you have not done it before and try to DIY.

Back - light problem. Check and replace damaged component/s at its back-light inverter board, or replace this board as card basis. If you wish to get some details; check the site linked here. Surf the site with patience. Pull up older posts. It will be best to replace the inverter board as card basis. http://electro-medical.blogspot.com/
To some model sets; especially LED back-lighted types; the back-light inverter circuit will be part of the main power supply board [SMPS]. In such cases, the power supply board might need replacement. To some models sets, the back-light inverter and SMPS section circuit will be integrated at its main board itself. If so; the main board should be replaced. To some models of sets, all these section circuit will be integrated at its main board. If this is the case, you have to replace the main board.

Invariably a bad or defective back light inverter in LCD tv.
or LED driver board.

Perform a flash light test and follow the steps as shown in the LCD LED TV Repair No Image Blank Black Screen Flashlight Test How to Fix...

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

Since you have replaced the LED board and you can still see a faint menu screen, this would indicate the LEDs have blown! Replace the backlight LEDs.