No Sound From External Output Device - Sharp LC-40LE820E Service Manual

LC-40/46/52LE820E, LC-40/46LU820E
Please Refer to "[External input HDMI-1/2/3/4] No picture on the display (10)".
Is there a audio input signal to pins (10/AUDIO_OUT_L) and (12/
AUDIO_OUT_R) of EXT1 (SC505)?
Is SC1-MUTE [118pins of IC3302 (Digital AV decode & Main
CPU)] or MUTE_A_ALL [21pin of IC2002 (UCOM)] at "H"?
Is there a audio output signal to pins (M30/TUNER_OUT_L) and
(M29/TUNER_OUT_R) of IC3302?
Check IC3302 and its peripheral circuits.
Does not the sound of the audio signal output to Headphone
mode go out?
Check whether it is selected "Headphone" by Headphone/Audio
out select under Menu-Setup-Option- Input terminal setting.
Is there a audio output signal to pins (2/HP/MONI_L) and (3/HP/MONI_R) of J504 (HEAD PHONE_OUTPUT/ AUDIO_OUTPUT terminal)?
Is the HP_PLUG signal input to [91/HP_PLUG] of IC4405 from
pin (6) of J504?
Is HP/MONI_MUTE [AJ11 of IC3302 (Digital AV decode & Main
CPU)] or MUTE_A_ALL [21pin of IC2002 (UCOM)] at "H"?
Is audio signal (HP_L/R) input to pins (M28/HP/MONI_L, M27/
HP/MONI_R) of IC3302?
Check IC3302 and its peripheral circuits.
No sound from external input devices (4)
Does not the sound of the audio signal input to HDMI1/2/3/4 go out?

No sound from external output device (1)

No audio signal output to EXT1 terminal.
NO
NO
NO
No sound from external output device (2)
No sound from HEAD PHONE_OUTPUT/ AUDIO_OUTPUT terminal.
YES
NO
YES
NO
NO
YES Check the setting of an external input device that connects with
EXT1.
YES Check the peripheral circuits of IC3302 and SC1-MUTE.
(Q502, D529 etc.)
YES Check the line between IC3302 and SC505.
Does not the sound of the audio signal output to Audio out
mode go out?
Check whether it is selected "Audio out" by Headphone/Audio out
select under Menu-Setup-Option-Input terminal setting.
Check the setting of an external input device that connects with
J504.
NO Check the line between J504 and IC4405.
YES Check the peripheral circuits of IC3302 and HP-MUTE_LINE.
(D527, Q506, etc.)
YES Check the line between IC3302 and J504.
7 – 5
YES
YES