3-14
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Only for training and service purposes.
ONE POINT REPAIR GUIDE
NO SOUND
There is no sound output in the Bluetooth function, repair the set according to the following guide.
5-5. BLUETOOTH FUNCTION
5-5-1. Solution
Replace MAIN board or bluetooth module.
5-5-2. How to troubleshoot (Countermeasure)
1) Check BT_RX, BT_TX signal to pin6, 4 of CN504.
If no signal, check the signal to pin4, 6 and pin10 (3.3 VA) 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 pin6, 4 of CN504 to pin L1,K1 to IC501 (DSP).
3) Check if MCS_BCK, MCS_LRCK & MIX_DATA IN is entered from IC501 to IC601.
If no signal, check +3.3 VA & +1.2 VA for IC501.
If it is abnormal, change replace it a new one.
4) Check the following I2S signal flow from IC501 to IC601.
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 on item 6-1.
If AMP is damaged, replace it with a new one.
5-5-3. Service hint (Any picture/ Remark)
IC501
IC601
PWM
MCS_BCK
MCS_LRCK
MIX_DATA0_OUT
AMP
B/T Module
BT_RX,
BT_TX
< Bluetooth function signal fl ow >
B
B
R222
R246
R5D1
R5D2
Q101
Q102
Q103
Q104
Q105
Q106
TP152
TP153
TP154
TP155
TP156
TP157
TP158
L108
L109
L110
L502
L505
L506
L507
L508
CN106
CN504
LG07
C508
C509
R739
C510
R740
R741
C512
R742
C513
R743
C514
R744
C515
C522
C524
C532
C753
C561
C758
C180 C181 C182
C183
C184
C185
C766
< MAIN board top view >
CN504
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