If the tv has never been service before you could have dust on the 3 tubes,this will decrease the brightness to the screen. try taking the front or back off & see if you can see the top of the picture tubes. remember to unplug the tv & to clean spray the cleaner on the colth , then clean the tup of the tube. never spary on the tube itself. hope this works for you. to remove the screens remove the front grill, then remove the screws @! the bottom of the screen & if i remember right the top just sits on a lip, so gently try to lift the screen up.careful, these screens are expensive & you will have 2 or 3 of them. some of them are really easy to scratch.
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