Help: Sony Wega TV KVXF21N90, no power

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can Any one help me?

Symptom: power LED stays lit but no raster, no sound

i've already change the Horizontal out transistor and what i think is the regulator, but still no luck.

i have two of this tv and same problem.

parts replaced:

STR F6654
D2578

thanks

help will be appreciated

thanks