Led Display Not Coming

A black screen can be caused by a number of problems:

Defective LED or strip of LEDs that provide the "back light" for the picture. This can be confirmed by using a a flashlight. Point the light at an angle to the screen (with it on) and you should see a shadow of the picture on the screen. This means that the panel is working and the backlight is not.

If the flashlight test fails, then it is possible that the "T-Con" board or the processing of the image is not working properly. This may be a separate board or part of the main board.

It is also possible that the power supply for the backlight has failed.

There is a slight possibility that the panel itself has failed too although this is rare.

Of the possibilities above, 1 or 3 are the most common and are usually easily fixed without too much cost. Some repair shops will only replace strips or boards. Others will repair the strips or boards. Replacing the parts will be more expensive than repairing them. Your mileage will vary depending upon what the individual shop can/will do.

When I get these sets in for repair, I always try to repair the boards. This results in a far less expensive repair that most of the time is well worth the repair cost. Note also that the screen size will make a big difference too. Repairing a set that is 32R43; or less is rarely worth the repair because of the labor costs involved. Just because the set is smaller does not mean that the repair takes less time so the labor rates for the smaller sets often make the repair not worth it.