LG OM7560 Service Manual page 36

NO SOUND
There is no sound output in the AUX Function, repair the set according to the following guide.
6-4. AUX FUNCTION
6-4-1. Solution
Replace IC201 on MAIN board.
6-4-2. How to troubleshoot (Countermeasure)
1) Check AUX_L/R signals to IC201 (pin23, 24).
2) Check if MCS_BCK, MCS_LRCK & MCS_MCLK are entered from IC501 to IC201.
3) Check if ADC_DATA is entered from IC201 to IC501.
  If no signal, check DVCC_5V & DVCC_3.3V (ADC) for IC201. If is NG, replace it a new one.
4) Check the following I2S signal flow from IC501 to IC601. (Refer to Item 6-2.)
  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 6-1.
  If AMP is damaged, replace it with a new one.
6-4-3. Service hint (Any picture/ Remark)
< AUX function signal fl ow >
ONE POINT REPAIR GUIDE
MCS_BCK: pin42 MCS_BCK: pin42
MCS_LRCK: pin43 MCS_LRCK: pin43
MCS_MLCK: pin44 MCS_MLCK: pin44
3-17
IC201 IC201
< MAIN board bottom view >