I'm sorry for the delay. The part that would be most likely to be causing the problem, would be the LED Engine, or the LED driver board.
Samsung BP94-02327A LED Driver Board
The LED drive board is unavailable anywhere I've checked. The other option is to purchase the entire LED Engine, but this part is very expensive, and these sets are basically obsolete. I hate telling people that about their very expensive TV's that develop these faults, but this set was plagued with problems that we've seen commonly in the field. The LED chips are prone to failure, the DMD is prone to failure, and the LED driver and Light Engine are also common problems.
The only source I could locate the entire engine from, is a site that is higher priced than most.
You would need to check the part number against the one in your set, as there were 2 revisions of this board.
If you need further assistance let me know and I will continue further.
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