No IC501 Is the voltage at pin 4 of IC501 DC18V ? Yes Check IC501 and associated circuit. 1 No 4 A Is the voltage at the point A in the Figure DC170V ? Yes Broken wire of R501 or short circuit on GND. R501 T501
No
Is the voltage at the point B in the Figure AC120V ?
Yes
Check R501 rectifying circuit. B
D501~D504
No RY101 Is the voltage at the point C in the Figure AC120V ? Yes Check associated circuit of the Relay. D No
C
L501
Is the voltage at the point D in the Figure AC120V ?
