Facing TV Problems? Ask a TV Technician.
Hello and sorry you're having problems. The screen getting darker is indicative of a lamp that's failing and needs to be replaced. When was the last time you replaced the lamp on the set please?
When the screen gets darker and darker- and the brightness has no effect, then the TV is telling you that the lamp is failing and should be replaced very soon (before it shatters). If you've replaced the lamp recently and it was not an OEM (original equipment) lamp, then this is also a common cause- as Mitsubishi sets require the correct OEM lamps when replacements are needed. The OEM lamp for your set can be purchased at the link below and will fix the problem:
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