LG OM5541 Service Manual page 24

There is no sound output in the TUNER FUNCTION, repair the set according to the
following guide.
(4) IN THE TUNER FUNCTION
[ Solution ]
Please check and replace IC201, TU500 on MAIN board.
[ How to troubleshoot (Countermeasure) ]
1) Check if TUNER_LR 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, SLT) are entered from IC501 to TU500.
If it doesn't work, replace TUNER with a new one.
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 +5 V & +3.3 V(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 4-(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 4-(1).
If AMP is damaged, replace it with a new one.
[ Service hint (Any picture / Remark) ]
TUNER
IC201
TUNER _L/R
A CS5346
12.288 MHz
FL ±
TAS5631BPHD
PWM
TAS5548
< AUX function signal fl ow >
ONE POINT REPAIR GUIDE
DSP IC501
MLC3730
176PIN BGA
TUNER_L to C214
< Main Board Top view >
3-9
TUNER_R to C215