Portable Function - LG TH900 Manual

NO SOUND
There is no sound output in the PORTABLE Function, repair the set according to the following guide.

6-6. PORTABLE FUNCTION,

6-6-1. Solution
Replace IC201 on MAIN board.
6-6-2. How to troubleshoot (Countermeasure)
1) Check if PT_LR signals to IC201 (pin9, 10).
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 with a new one.
4) Check the following I2S audio 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.
6-6-3. Service hint (Any picture/ Remark)
< PORT. IN function signal fl ow >
ONE POINT REPAIR GUIDE
3-19
IC201 IC201
PT_L: pin9 PT_L: pin9
PT_R: pin10 PT_R: pin10
< MAIN board bottom view >