NO.14 CAPSTAN TROUBLESHOOTING FLOW CHART NO.16 DRUM MOTOR TROUBLESHOOTING(2)
drum runs only for a few seconds. The capstan motor fails to run.
Replace IC706.
Check IC701. NO DC given out pin(29) of IC701?
Is the voltage more than about 2.6V NO
Is drum PG signal given out from the NO Check peripheral circuit of pins (4), (5) pin (7) IC706? and (6) of IC706.
YES
Is the supply voltage of 5V fed to NO Check PC 5V line. YES YES pin(8) of AC connector?
Check drum motor.
YES
Is voltage more than 2.6V DC the AC connector NO Is drum PG signal fed to pin(66) Check line between pin(7) of IC706 sent in pin(4) AC connector? pin(29) IC701? IC701? and pin(66) of IC701.
YES YES
voltage pin(3) AC Check line between the pin(92) of Is head switching pulse sent out from NO the pin(23) of IC701? Check MOTOR Vcc line and motor
YES
Check IC701. connector 1.6~2.7V? IC701 and pin(3) of AC connector.
YES
Is the supply voltage of 12V/20V fed NO voltage selector circuit. Replace IC701. to pin(5) of AC connector? (Q995, 996)
YES
FLOW CHART NO.17 HEAD SWITCHING PULSE TROUBLESHOOTING.
No head switching pulse.
Replace capstan motor.
41
Is the drum motor rotating? NO IC701, respectively? YES
Check PC 5V line.
FLOW CHART NO.15 DRUM MOTOR TROUBLESHOOTING(1)
See FLOW CHART NO.15, 16 (DRUM MOTOR TROUBLESHOOTING(1), (2))
YES
The drum motor fails to run.
Is the voltage more than about 2.6V NO Is the PG signal and drum FG DC given out pin(46) of IC701? Replace IC701. signal present on pins(66) and (65) of
Check IC701. YES
Is the supply voltage of 5V fed to pin
NO NO D-FG
(3) of IC706?
YES about 5Vp-p
DC given out pin(2) of IC706? and pin(2) of IC706.
NO Is the voltage more than about 2.6V Check line between pin(46) of IC701 D-PG
YES about 5Vp-p
Check M 12V line. pin(21) of IC706? Check line between IC706 and
