Chosen Solution
hello my samsung tv screen started showing black spots at bottom and at the sides a month back and now the screen has gone dark like the brightness level is at the lowest but its not black. what could be the reason and what can i do to fix it? Update (12/17/2021) model is Samsung UN40K5100AFXZA LED HDTV
Naveen verma, two things that could be causing this. Bad backlight strips or a bad power board. You would have top remove teh back cover from your TV and take a look at the power board. Find the backlight LED connectors and measure the voltages on that. Let us know what you find. With the size of this TV I would expect something around 400VDC on those. What makes me think it is more likely the backlight strips is this”started showing black spots at bottom” which could have been caused by a bad backlight array. To change that you will have to dismantle your TV as well as the LCD panel. Not a terrible job but you will need 2 people to do so since the panel is large and may flex, so make sure you have an extra pair of hands. You’d be looking at a repair similar to this LG 55UH6150 backlight LED replacement
