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3-24
ONE POINT REPAIR GUIDE
NO SOUND
There is no sound output in the Bluetooth function, repair the set according to the following
guide.
10-6. BLUETOOTH FUNCTION
10-6-1. Solution
Replace IC501 on the MAIN board or B/T module on the Front Panel.
10-6-2. How to troubleshoot (Countermeasure)
1) Check BT_RX, BT_TX signal to pin4, 6 of CN504.
If no signal, Check the signal to pin4, 6 and pin10 (+3.3 V) of on the Bluetooth module and cable
connection state.
If there are no signal out from module, replace new module.
2) Check if BT_RX/TX is entered from pin4, 6 of CN504 to pin K1, L1 to IC501 (DSP).
3) Check the following I2S signal flow from IC501 to IC600.
If there is any trouble, check the power for each IC. If the signals are abnormal, replace it a new one.
4) Check if the digital audio AMP block is okay.
If AMP is damaged, replace it with a new one.
10-6-3. Service hint (Any picture / Remark)
IC501
MLC3730
IC202
PS9860
PWM
MCS_BCK
MCS_LRCK
MIX_DATA_OUT
IR AMP
IRF6775
B/T Module
BT_RX,
BT_TX
< Bluetooth function signal
fl
ow >
< MAIN board top view >
CN504
CN504
BT_RX. pin6
BT_RX. pin6
BT_TX. pin4
BT_TX. pin4
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 ...