Here is the power supply circuit
DOWNLOAD DATASHEET NCP1392-D :
NCP1392-D.PDF
Try replacing the fuse, transistors M1, M2 and U1 - NCP1392D, R108, R109.
Take photos of the power supply board.
You can replace NCP1392D with L6571
Circuit L6571
DOWNLOAD DATASHEET L6571:
l6571.pdf