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3-17
ONE POINT REPAIR GUIDE
NO SOUND
There is no sound output in the AUX FUNCTION, repair the set according to the fol-
lowing guide.
6-2. IN THE AUX FUNCTION
6-2-1. Solution
Please check and replace IC202 on MAIN board.
6-2-2. How to troubleshoot (Countermeasure)
1) Check AUX_L/R signals to IC202 (Pin7, 8).
2) Check if MCS_BCLK, MCS_LRCLK, & MCS_MCLK are entered from IC501 to IC202.
3) Check if ADC/MIC_DATA is entered from IC202 to IC501.
If no signal, check +5 V & +3.3 V(ADC) for IC202. If is NG, 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. The power is normal but, if the signal waveform to
the IC is distorted or no signal, replace it with a new one.
5) Check if the digital audio AMP block is okay.
If AMP is damaged, replace it with a new one.
6-2-3. Service hint (Any picture / Remark)
w{sGGYX
w{yGGYY
pjYWY
hkjVtpjkh{hGGGyYX\
tjzijrGGyYX]
tjzsyjrGGyYX`
tjztjsrGGyYYX
AUX
{T
IC501
MLC3730
IC600
TAS5548
PWM
MCS_BCK
MCS_LRCK
IC202
CS5346
ADC/MIC_DATA
MCS_MCLK
AUX_L/R
IR AMP
IRF6775
MIX_DATA_OUT
< Signal check point >
< AUX 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 ...