Why my tv is not on

@shyamsingh84539 couple of things we need to know. First we need to have your Mi TV's exact model number. Next we need to know if anything happened to it and what you have tried. Thirs, you do want to proceed as addressed in the comment. Post pictures of all of your boards as well as the interconnecting ribbon cables.

Until we have more information from you give this a try. Unplug everything (cable box, SAT box, game console etc.)that is plugged in the back of your TV. Last unplug the TV and push the power button for about one minute. Now connect one local video input source. Something like a DVD/BR player or a game console. Once that is connected, plug your TV in last and try to turn it on. Let us know what happens.

If that does not work, unplug your TV, remove the back cover and let us see all of your boards etc.

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