5 stars on this manual since it is the complete version, not the half manual you find free for download all over the web. Good job.
Text excerpt from page 15 (click to view)
Is the voltage at C501 DC24.0V ?
Check the circuit after C501.
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
Is the voltage at the point B in the Figure AC120V ?
Check D501 ~ D504 rectifying circuit. B
Is the voltage at the point C in the Figure AC120V ?