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     LC-42SD1E/RU

4 – 5

                                             
No sound from EXT5 (AUDIO) connecting an external input 
device.

                                             
<EXT5>
Is HDMI-L audio signal sent from J2701 to pin (14) of IC2704?
Is HDMI-R audio signal sent from J2701 to pin (5) of IC2704? 

YES

Is HDMI-L audio signal sent to pin (10) of IC3002? 
Is HDMI-R audio signal sent to pin (9) of IC3002?

NO

Check output of pins (13) and (3) of IC2704 and peripheral 
circuits. 

YES

Check that Option-HDMI Setup-Audio select is set to “Analog”.

                                            

OK

Is the audio signal properly sent from pins (28) and (27) of 
IC3002?

NO

Check IC3002 or peripheral circuits.

YES

Is the audio signal of pins (1) and (7) of IC303 (OP-AMP) sent 
properly?

NO

Check IC303 or peripheral circuits.

YES

Is the audio output signal of pins (13) and (16) of IC302/IC301 
(MAIN-AMP) normal?

NO

Check IC302/IC301 (MAIN-AMP), HEADPHONE and peripheral 
circuits.

YES

Check CONNECTOR (P301) and Speaker (right and left).

LC-42SD1E/RU

4 – 6

                                             
No audio output from the headphones.

                                             
Is there audio output on pins (2) and (3) of the headphone 
terminal (J1301)?

NO

Is audio input/output signal of pins (3) and (5)/(1) and (7) of IC303 
(OP-AMP) normal? 

NO

Is audio output signal (SPK-OUT L/R) properly sent from pins 
(28) and (27) of IC3002 (VCT)?

NO

Check audio input signal of pin (31) of IC3002 (VCT), pins (18) 
and (33) of the power line, pins (84) and (83) of I2C-LINE, and 
peripheral circuits.

                                            
No audio output from EXT1 (SCART) terminal.

                                            
Checklist: 
1) Is the MUTE button on the remote control set to ON? 

••• Set to OFF.

2) Check the connection to external devices. 

••• Is there any improper connection?

                                            
Is audio signal sent to pins (3) and (1) of EXT1 (J1101)?

YES

Check the connection to EXT1 (J1101) and external devices.

                                            

NO

Is S-MUTE-LINE [IC1710 (pin 100)] at H?
(Check Q1106/Q1105 operation.) 

                                            

NO

Is audio signal sent from pins (24) and (23) of IC3002? 

NO

Check the power supply 8/5 V pins (18) and (33) of IC3002 and 
peripheral circuits.

YES

Check the audio signal output line from pins (24) and (23) of 
IC3002 to pins (3) and (1) of EXT1.

     LC-42SD1E/RU

4 – 7

                                            
No audio output from EXT2 (SCART) terminal.

                                            
Checklist: 
1) Is the MUTE button on the remote control set to ON? 

••• Set to OFF.

2) Check the connection to external devices. 

••• Is there any improper connection?

                                            
Is audio signal sent to pins (24) and (22) of EXT2 (J1101)?

YES

Check the connection to EXT2 (J1101) and external devices.

                                            

NO

Is S-MUTE-LINE [IC1710 (pin 100)] or S2-MUTE-LINE [IC3003 
(pin26)] at H? 
(Check Q1102/Q1101 operation.)

                                            

NO

Is audio signal sent from pins (22) and (21) of IC3002?

NO

Check the power supply 8/5 V pins (18) and (33) of IC3002 and 
peripheral circuits.

YES

Check the audio signal output line from pins (22) and (21) of 
IC3002 to Q1103/Q1104/Q1201/Q1202.

                                            
No audio output from AUDIO OUTPUT terminal.

                                            
Checklist: 
1) Is the MUTE button on the remote control set to ON? 

••• Set to OFF.

2) Check the connection to external devices. 

••• Is there any improper connection?

                                            
Is audio signal sent to pins (13) and (15) [L/R (white) (red)] of 
AUDIO OUTPUT terminal (J1201)?

YES

Check the connection to AUDIO OUTPUT terminal (J1201) and 
external devices.

                                            

NO

Is S-MUTE-LINE [IC1710 (pin 100)] at H?
(Check Q1204/Q1203 operation.) 

                                            

NO

Is audio signal sent from pins (22) and (21) of IC3002?

NO

Check the power supply 8/5 V pins (18) and (33) of IC3002 and 
peripheral circuits.

YES

Check the audio signal output line from pins (22) and (21) of 
IC3002 to Q1103/Q1104/Q1201/Q1202.

LC-42SD1E/RU

4 – 8

The unit does not enter the DTV mode. Or, the DTV menu does 
not appear.

YES

Go to “The unit does not enter the DTV mode. Or, the DTV menu 
does not appear.”

NO

No video output during DTV reception.

YES

Go to “No video output during DTV reception.”

NO

No audio output during DTV reception.

YES

Go to “No audio output during DTV reception.”

Digital UNIT:
Is a voltage supplied from IC4701(3.3V-REG)/IC4704(1.8V-
REG)?

NO

Check peripheral circuits of IC4701/IC4704 and pin(7) of IC4701.

YES

Do X4001/X4002 oscillate?

NO

Check peripheral circuits of X4001/X4002.

YES

D-TUNER UNIT:
Is a voltage of 5V supplied from IC205(SW) and IC206(SW)?

NO

Check peripheral circuits of IC205/IC206.

YES

Is a voltage applied to pin(20) (I2CSEL) of P202?
(High=3.3V)

NO

MAIN UNIT:
Check around the pin (12) of IC1710(FPGA).

YES

Is CLK/DATA signal sent to pins (21) and (22) of P202 and pins 
(1) and (13) of IC204 (COFDM).

NO

Check peripheral circuits of IC202(COFDM)/ IC4001(D-Proces-
sor).

YES

Does X202 oscillate?

NO

Check peripheral circuits of X202.

YES

Check IC202(COFDM)/IC4001(D-Processor).