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3-29
ELECTRICAL TROUBLESHOOTING GUIDE
No AMP output
Check PFC P.CTL from
μ
-com.
Check AMP P.CTL from
μ
-com.
Replace D908, Q955, PC903.
Replace D908, Q956, PC902.
Replace F911.
Check or replace
IC904, Q907 ~ Q910.
Check or replace IC902 and
Check Q911 ~ Q914 gate(Pin2)
Components (Resistors, Diodes).
Q911 ~ Q914 OK?
Replace Q911 ~ Q914.
Check or replace D953 ~ D956.
Check line of MAIN PCB is short or not.
Is the
C904, C905 voltage
about 380 V?
F911 normal?
PFC P.CTL OK?
AMP P.CTL
OK?
Is the
VCC 12V supplied to
IC904 Pin16?
Is the
VCC 12V supplied to
IC902 Pin8?
NO
YES
NO
NO
NO
NO
YES
NO
YES
YES
YES
YES
NO
NO
Summary of Contents for CM9730
Page 11: ...MEMO 1 10 ...
Page 13: ...MEMO 2 2 ...
Page 59: ...MEMO 3 42 ...
Page 83: ...3 89 3 90 2 MAIN P C BOARD TOP VIEW ...
Page 84: ...3 91 3 92 MAIN P C BOARD BOTTOM VIEW ...
Page 85: ...3 93 3 94 3 VFD P C BOARD ...
Page 86: ...3 95 3 96 4 MAIN VOLUME P C BOARD 5 MIC P C BOARD ...
Page 87: ...3 97 3 98 6 JOG P C BOARD 7 USB P C BOARD 8 TUNER P C BOARD ...
Page 89: ...3 101 3 102 MEMO MEMO ...