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why is there a sick black line going down the center of my television Update (08/16/2018) 55 inch samsung smart tv curved made 2016 model number un55k6250

Other then the black line the tv is best tv i have ever had

@bartomike5 that could be a t-con board error as well as a panel error and many more things. Let us know what model your TV is and what you have checked. Most likely you will have to remove the back of your TV and make sure that all the wiring is connected and check the boards for any obvious damage. Post some pictures of the complete board layout and each board with your question so that we can see what you see. Adding images to an existing question