LG CJS45F Service Manual page 45

NO SOUND
There is no sound output in the PORTABLE FUNCTION, repair the set according to the following
guide.
5-6. IN THE PORTABLE FUNCTION
5-6-1. Solution
Please check and replace IC202 on MAIN board.
5-6-2. How to troubleshoot (Countermeasure)
1) Check PT_L/R signals to IC202 (Pin1, 2).
2) Check if MCS_BCK, MCS_LRCK, & MCS_MCLK are entered from IC500 to IC202.
3) Check if ADC_DATA is entered from IC202 to IC500.
  If no signal, check +5 V & +3.3 V(ADC) for IC202. If NG, replace it a new one.
4) Check the following I2S signal flow from IC500 to IC700. (Refer to Item 5-1.)
  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. Refer to "Digital Audio AMP" guide on Item 5-2.
  If AMP is damaged, replace it with a new one.
5-6-3. Service hint (Any picture / Remark)
PTB_L/R
IC201
Portable
12.288 MHZ
PWM
< PORTABLE function signal fl ow >
ONE POINT REPAIR GUIDE
DSP IC501
176 PIN BGA
Audio DSP-1
USB 2.0 OTG
SRAM29KB
Main Processor
DSP
Audio DSP-0
I-Cache 8KB
USB 1.1 133Mhz
16KB SRAM29KB
ARM DSP
Host/Device
I-Cache D-Cache 8KB
926EJS
I-Cache 8KB
133Mhz
16KB
400Mhz
SRAM (10K)
D-Cache 8KB
D-Cache
I2S (7.1ch)
SDRAM
Controller Boot ROM (20KB) GDMA 2ch
SPDIF (Rx, Tx)
Interrupt
ADPCM
controller
CDROM x8 speed
Decoder PLL
ADC (12bit*5ch) RTC & Wake up
Clock Controller
GDMA 3ch
Timer, Watchdog UART 4ch (Max)
Reset Controller
NAND Controller GPIO (72 Max) I2C 2ch
within BCH codec
Test Controller
SPI 4ch (Max) SDHC-SDIO 4ch (Max)
14bits ECC
FR,FL
Woofer
< Signal check point >
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