If you want you can disregard all the warnings but these can kill folk. I see over in AVSFORUM they get into discussing TV repair. So that's my suggestion if this is you beginning your career as a TV repair person. Try AVSFORUM next.
I have a sony KDP-57ws550 and when I pressed the power button the standby led blinks 8 times.The diagnostic code points to audio board or high voltage circuit.I opened the tv and found out nothing wrong in that area because the main power converter IC6400 is not switching at all.The voltage on pin#1 of IC6400 is remain 0.04 volts when I pressed the power button.I trace back to Q6403 (The photo coupler driver) and found out that base voltage status(0v) doesn't change while power button is pressed.That means MAIN_ON voltage is not coming there.My problem is I don't know where is the source of that voltage?Is that from MA(MIcro) board) CN0002 to CN5008?.Where does that goes to?Thank you very much