Is the voltage more than about 2.6V NO DC given out pin(25) of IC701?
Is drum PG signal given out from the NO Check peripheral circuit of pins (22), (23) pin (33) IC706? and (24) of IC706.
Check IC701. NO
YES
Is the voltage more than about 2.6V Check line between pin(25) of IC701
NO YES DC given out and pin(12) (sankyo IC) of AC YES
of AC (kumaconnector or pin(32) (kumagaya IC) Check drum motor. gaya IC) IC706? of IC706.
Is drum PG signal fed to pin(47) of
Is the supply voltage 12V fed to NO IC701? and pin(47) of IC701. Check M 12V line. pin(8) (sankyo IC) of AC connector or pin(20) (kumagaya IC) of IC706? YES
NO YES Is head switching pulse sent out from
YES NO Check line between pin(33) of IC706
the pin(18) of IC701? Replace drum motor.
YES
Check IC701.
Replace IC701.
40
FLOW CHART NO.15 HEAD SWITCHING PULSE TROUBLESHOOTING.
Is the drum motor rotating? NO
YES
No head switching pulse.
See FLOW CHART NO.14, 15 (DRUM MOTOR TROUBLESHOOTING(1), (2))
Is the PG signal and drum FG YES
Replace IC701. signal present at pin(47) of IC701?
NO
D-PG 2.5V D-FG 2.5V
Check line between IC706 and IC701.
NO
Are the PG signal and drum YES FG signal present on pins (33), (34) of IC706? Check peripheral circuit of IC706.
