Shorted Vertical IC

Can anyone help me,recently a customer sent me a TCL model CRT TV with only one horizontal line.After checking I found that the vertical IC STV9302A at fault,replace the IC solved the problem but after 1 hour testing the vertical IC blown again and now with only standby voltage and B+ voltage present but with no high voltage.Please help me.

Model number of set?

Get the datasheet for the IC and verify voltages.

Have a scope? Verify sawtooth pattern across yoke resistor is clean / well formed. See examples in datasheet for signal and current waveforms.

High voltage correct?

Check ESR of electrolytic caps in area of IC.

Obtain IC from reputable source?

Is IC mounted correctly with proper heatsink compound?

Toast

I always change the yoke coupling caps...there's probably 3 caps next to the vertical output ic.
also check any diodes nearby. After you remove the bad ic you might want to check the Vcc or supply voltage. Go to datasheetarchive to find a data sheet to see which pin it is.