LG CMS9540F Service Manual

3-18
ONE POINT REPAIR GUIDE
NO SOUND
There is no sound output in the PORT. IN FUNCTION, repair the set according to the
following guide.
6-3. IN THE PORT. IN FUNCTION
6-3-1. Solution
Please check and replace IC202 on MAIN board.
6-3-2. How to troubleshoot (Countermeasure)
1) Check PT_L/R signal from JOG board to MAIN board.
2) Check if PT_LR is entered pin 4 & 5 of CN3J01  pin 4 & 5 of CN3V02  Pin21 & 20 of CN3V01.
3) Check POT_L/R signals to IC202(pin21, 22).
4) Check if ADC_BCK, ADC_LRCK, & DAC_MCLK are entered from IC501 to IC202.
5) Check if ADC_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.
6) 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.
7) 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.
6-3-3. Service hint (Any picture / Remark)
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pjYWY
hkjVtpjkh{hGGGyYX\tjzijrGGyYX]
tjzsyjrGGyYX`
tjztjsrGGyYYX
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IC501
MLC3730
IC600
TAS5548
PWM
MCS_BCK
MCS_LRCK
IC202
CS5346
POT. IN
ADC/MIC_DAT A
MCS_MCLK
POT_L/R
VOLUME
Board
IR AMP
IRS2092+IRF6775
MIX_DATA_OUT
< Signal check point >
< PORT. IN function signal fl ow >

LG CMS9540F Specifications

General

Brand	LG
Model	CMS9540F
Category	Stereo System
Language	English