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3-25
ELECTRICAL TROUBLESHOOTING GUIDE
1. POWER SUPPLY ON SMPS BOARD
YES
YES
YES
YES
YES
No output 5.6 VA
No 12 V
Power line of MAIN PCB is short.
Replace F901 (same fuse).
Check or replace D962.
Is D960/ D961 normal?
Replace BD901 or BD902.
Check P_CTL from
μ
-com.
Check and replace IC951.
Or check line of
MAIN
PCB is short or not.
Check or replace D960/ D961.
NO
NO
NO
NO
NO
Is the F901 normal?
Is the
VCC 13 VA supplied to IC951
pin2?
Is the VCC
(11 V ~ 25 V) supplied to IC901
pin4?
Is BD901 or BD902 normal?
Is there
‘H’ signal at IC951
pin1?
Summary of Contents for CM9750
Page 15: ...2 2 ...
Page 19: ...4 SPEAKER SECTION A60L A60R ...
Page 75: ...3 71 3 72 PRINTED CIRCUIT BOARD DIAGRAMS 1 SMPS P C BOARD TOP VIEW ...
Page 77: ...3 75 3 76 2 MAIN P C BOARD TOP VIEW ...
Page 78: ...3 77 3 78 MAIN P C BOARD BOTTOM VIEW ...
Page 79: ...3 79 3 80 3 FRONT P C BOARD TOP VIEW ...
Page 80: ...3 81 3 82 FRONT P C BOARD BOTTOM VIEW ...
Page 81: ...3 83 3 84 4 FRONT_CTRL P C BOARD TOP VIEW BOTTOM VIEW ...