Is the voltage at the point (A) in the Figure DC160V ?
Yes
Is the voltage at pin G of Q501 DC5V ?
Yes
Check Q501 and associated circuit.
No
No
Check Q502 and associated circuit.
T502 A Is the voltage at the point (B) in the Figure DC164V ? No Yes Check R501 and R541. D Q501 S Is the voltage at the point (C) in the Figure AC120V ? Yes Check the rectifying circuit. Q502 R501 IC501 3 B 5 8
G
No D501~D504 Is the voltage at the point (E) in the Figure AC120V ? Yes Broken wire of L501.
No
C
Is the voltage on both ends of S501 AC120V ? No Broken wire of AC cord or check S501.