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3-22
ONE POINT REPAIR GUIDE
NO SOUND
There is no sound output in the TUNER function, repair the set according to the following guide.
10-4. TUNER FUNCTION
10-4-1. Solution
Replace IC201, TU500 on MAIN board.
10-4-2. How to troubleshoot (Countermeasure)
1) Check if TUNER_L/R is entered from pin1 & 3 of TU500 to IC201(pin26, 27).
If no signals, Check +3.3 V for Tuner power.
Check if the Tuner control signals (CLK, DAT, CE, RST, GPO2) are entered from IC501 to TU500.
If it doesn’t work, replace TUNER with a new one.
2) Check if ADC_BCK, ADC_LRCK & DAC_MCLK are entered from IC501 to IC201.
3) Check if ADC_DATA is entered from IC201 to IC501.
If no signal, check +5 V & +3.3 V (ADC) for IC201. If is NG, replace it a new one.
4) Check the following I2S audio signal flow from IC501 to IC202.
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.
10-4-3. Service hint (Any picture / Remark)
{TG
IC501
MLC3730
IC202
PS9860
PWM
MCS_BCK
MCS_LRCK
{
IC201
CS5346
TUNER
ADC/MIC_DATA
MCS_MCLK
TUNER_L/R
IR AMP
IRF6775
Jack
Board
MIX_DATA_OUT
< TUNER function signal
fl
ow >
< MAIN board bottom view >
IC201
IC201
ADC/MIC_DATA to R212
ADC/MIC_DATA to R212
MCS_BCK to R213
MCS_BCK to R213
MCS_LRCK to R215
MCS_LRCK to R215
MCS_MCLK to R216
MCS_MCLK to R216
TUNER_L/R
TUNER_L/R
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 ...