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< Signal check point >
ONE POINT REPAIR GUIDE
NO SOUND
There is no sound output in the BLUETOOTH FUNCTION, repair the set according to
the following guide.
6-6. IN THE BLUETOOTH FUNCTION
6-6-1. Solution
Please check and replace IC501 on MAIN board and Bluetooth module on front panel.
6-6-2. How to troubleshoot (Countermeasure)
1) Check BT_RX, BT_TX signal to Pin5, 7 of CN504.
If no signal, check the signal to Pin5, 7 and Pin1(+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 Pin5, 7 of CN504 to Pin169, 170 to IC501 (DSP).
3) Check if MIC_BCK, MIC_MLCK & MIC_O_DATA is entered from IC501 to IC600.
If no signal, check VCC12(+1.2 V) for IC501. If it is abnormal, change replace it a new one.
4) 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.
5) Check if the digital audio AMP block is okay. Refer to “Digital Audio AMP” guide.
If AMP is damaged, replace it with a new one.
6-6-3. Service hint (Any picture / Remark)
IC501
MLC3730
IC600
TAS5548
PWM
MCS_BCK
MCS_LRCK
MIX_DATA_OUT
IR AMP
IRF6775
B/T Module
BT_RX,
BT_TX
< BLUETOOTH function signal
fl
ow >
Summary of Contents for CM8440
Page 15: ...MEMO 2 2 ...
Page 19: ...A60L 4 SPEAKER SECTION 4 1 FRONT SPEAKER CMS8440F LEFT SPEAKER ...
Page 20: ...A60R FRONT SPEAKER CMS8440F RIGHT SPEAKER ...
Page 21: ...A90 4 2 SUBWOOFER SPEAKER CMS8440W ...
Page 73: ...3 65 3 66 PRINTED CIRCUIT BOARD DIAGRAMS 1 SMPS P C BOARD TOP VIEW ...
Page 74: ...3 67 3 68 SMPS P C BOARD BOTTOM VIEW ...
Page 75: ...3 69 3 70 2 MAIN P C BOARD TOP VIEW ...
Page 76: ...3 71 3 72 MAIN P C BOARD BOTTOM VIEW ...
Page 77: ...3 73 3 74 3 FRONT VOLUME P C BOARD ...
Page 78: ...3 75 3 76 4 MIC PORTABLE P C BOARD MEMO ...
Page 79: ...3 77 3 78 MEMO MEMO ...