You'll find numerous reports of the same thing. If you hear the normal sounds when you press buttons on the remote and can see any image whatsoever if you shine a bright light on it, your backlight has probably failed like most of the others. If it has, you can research how to repair a backlight in a TCL TV to see if you're up to the challenge.
One thing to try is to leave it unplugged for a few hours or overnight. If the picture comes back when you try it again, turn down the brightness especially if it's on the highest level.
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