This set is known for some common issues--one is a built in feature where it will try to come on three times and if fails goes into shutdown.
The most common issue is bad solder connections where the high voltage transformer is soldered into the board and right around it.
It has some convergence issues but set will still play.
On the board where the transformer is located it can fail and some other parts (output transistor shorts).
It is not repair friendly as all parts are specialized.
If going to look--look for the bad connections first.
photo here of typical high voltage transformer:
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