LC-19D1EBK (serv.man5). Troubleshooting Table - Sharp TV Service Manual (repair manual). Page 8

LC-19D1E/S-BK/WH

4 – 8

                                            
No sound from EXT4 (MDMI-AUDIO) connecting an external 
input device.

                                            
<EXT4>
Is HDMI-L audio signal input from J504 to pin (8) of IC301 (A-
Selector)? 
Is HDMI-R audio signal input from J504 to pin (5) of IC301 (A-
Selector)?

YES

Is HDMI-L audio signal input to pin (42) of IC501 (AV-SW)?
Is HDMI-R audio signal input to pin (40) of IC501 (AV-SW)? 

NO

Check Connector SC1202 pins (9) and (10), Connector SC501 
pins (9) and (10) and short circuit.

YES

Is the audio signal (TERMINAL-L/R) properly output from pins 
(34) and (33) of IC501 (AV-SW)? 

NO

Check the Power supply input of pin(38) of IC501, or SDA2/SCL2 
signal of pins (28) and (29) or peripheral circuits.

YES

Is the audio signal (LOUT2/ROUT2)  output properly from pins 
(25) and (23) of  IC302  (A-CODEC) ?  

NO

Check pins (1) and (4) of  IC302 (A-CODEC) , pins (11) and (12) 
of  Connector SC1202, audio-mute line (Q301/Q302) or periph-
eral circuits. 

YES

Is the audio  signal L-CH output to  pins  (44-45) and (40-41)  of  
IC303 (POWER-AMP)? Is the audio  signal R-CH output to  pins  
(20-21) and (16-17) of  IC303 (POWER-AMP)  normally ?    

NO

Check UR12V power supply input pins (47) and (14) of  IC303 
(POWER-AMP) or peripheral circuits. 

YES

Is the audio signal of pins (1)-(4) of  SP-Connector (P301)  prop-
erly output?

NO

Check SP-CONNECTOR (P301) and short circuit.

YES

Check SP-BOX (right and left) and WIRE HARNESS.