Sharp LC-42SV32B Service Manual page 33

Does not the sound go out though the picture has come out when TV is received?
MAIN UNIT:
Is the IF signal output from pin (1/2/4/5) of Tuner (TU101)?
Is the IF signal sent to pin (AD17/AE17) of IC U401?
Refer to "No sound output in all modes".
Does not the sound of the audio signal input to Component go out?
MAIN UNIT:
Is the audio signal properly sent to pin (8)(YPbPr_L_In) and pin
(11)(YPbPr_R_In) of CN111?
Is the audio signal properly sent to pin (AC20) (YPbPr_L_In) and
pin (AE23) (YPbPr_R_In) of IC U401?
Refer to "No sound output in all modes".
Does not the sound of the audio signal input to (Composite, Y/C) go out?
MAIN UNIT:
Is the audio signal properly sent to pin (4) (SIDE_AudioLIN) and pin
(7) (SIDE_AudioRIN) of CN128?
Is the audio signal properly sent to pin (AC21) (AV2_L_In) and pin
(AE24) (AV2_R_In) of IC U401?
Refer to "No sound output in all modes".
No sound (during the reception of TV broadcasting)
↓
↓
↓YES
↓YES
No sound from external input devices (1)
↓
↓
↓YES
↓YES
No sound from external input devices (2)
↓
↓
↓YES
↓YES
NO
Check the tuner and its peripheral circuits. Replace as required.
NO
Check IC U401 its peripheral circuits.
NO
Check the connection to CN111 and the external input device.
Check the line between CN111 and IC U401.
NO
NO
Check the connection to CN128 and the external input device.
NO Check the line between CN128 and IC U401.
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LC-42SV32B