There is this Samsung DVD which blew up due to over voltage in the mains supply. I have checked all the necessary and almost all components on the board and they are all in good oder. I even replaced some of them just to be sure but still it will not switch on. BTW the Fuse blew and was replaced with the same type and rating. I hear fiiin sound probably from the transformer and the pilot lamp (LED) does not come on . What might be Wrong? Please help.
First of all rule out shorts on the primary and secondary sides. Seems as if you've pretty much done this on the primary side - do check all rectifier diodes AND ZENER DIODES on the secondary side. Confirm the switcher is running, and that nothing is loading down any of the power supply lines. Typical readings might be 3.3 volts, 9 or 14 volts, possibly a negative voltage matching that. You could have an open resistor. You may very well need a 'scope, service manual, and an ESR meter for further troubleshooting.
Mark Z.
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