3-30
ELECTRICAL TROUBLESHOOTING GUIDE
USB FUNCTION
Replace IC312.
NO
IC312 USB Power
+5 VU OK?
YES
A
A
When insert USB,
IC501 pin U7, U8, A7, A8
USB_D signal OK?
NO
YES
YES
YES
YES
AUX FUNCTION
Check audio cable.
Replace IC201.
Check IC501.
NO
NO
NO
IC201
pin23, 24 AUX input signal
OK?
IC201
pin41 ADC_DATA_IN output
signal OK?
IC201
pin42, 43, 44 I2S input signal
OK?
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 ...