Sharp Lcd Tv with no power repaired

The tv was hit by a high voltage and fails to power on.This is the internal structure of the tv









since it is a dead set the first thing is to check the power board.The board is intact without any burnt component on it.The reason why I am expecting to see a burnt component is because it was hit by a high voltage but was amazed when I could not found none.I tested all components at power and all tested fine except for the power ic which cannot be tested with the multimeter.
I set my meter to the volt range and test.It was then I detect a flunctuating voltage at one of the terminals of this ic









Thinking maybe this ic is bad,I decide to make test at the secondary side of the sm transformer.It was there I detect the same fluctuating voltage at the rectifier diodes terminal at this side.I tested the diodes and detect that one of it is faulty











I replace this diode with the same specification.After the replacement I power the tv and it works perfectly.

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