Sharp LC-52DH77E/RU/S, Service Manual

Page: 39 / 98

LC
-
52DH77E/RU/S
4 – 5
The audio signal is not output (1)
No audio signal output from EXT1/EXT2 terminal.
Is there a audio input signal in pins (3/TUNER_OUT_L) and (1/
TUNER_OUT_R) of EXT1 (SC503)?
YES Check the setting of an external input device that connects with
EXT1.
Is there a audio input signal in pins (3/MONITOR_L) and (2/
MONITOR_R) of EXT2 (SC502)? YES Check the setting of an external input device that connects with
EXT2.
NO
Is (AF11/SC1-MUTE) of IC3302 (Digital AV decode & Main CPU)
at H? YES Check the peripheral circuits of IC3302 and SC1-MUTE.
(Q502, D529 etc.)
Is (AG11/SC2-MUTE) of IC3302 (Digital AV decode & Main CPU)
at H? YES Check the peripheral circuits of IC3302 and SC2-MUTE.
(Q501, D528 etc.)
NO
Is there a audio output signal in pins (N27/TUNER_OUT_L) and
(N28/TUNER_OUT_R) of IC3302 (Digital AV decode & Main
CPU)? YES Check the line between IC3302 and SC503.
Is there a audio output signal in pins (M30/MONITOR_L) and
(M29/MONITOR_R) of IC3302 (Digital AV decode & Main CPU)? YES Check the line between IC3302 and SC502.
NO
Check IC3302 and its peripheral circuits.
The audio signal is not output (2)
No audio signal output from AUDIO_OUTPUT terminal.
Is audio signal (L/R) output to pins (2, 4) of AUDIO_OUTPUT ter-
minal (J506)?
YES Check the connection to AUDIO_OUTPUT terminal and external
input devices.
NO
MONITOR_MUTE signal [AF13/MONI_MUTE] of IC3302 (Digital
AV decode & Main CPU) or MUTE_A_ALL signal [21pin of
IC2002 (UCOM)] will be “H”? YES Check the peripheral circuits of IC3302 and MUTE-A_ALL_LINE.
(D526, etc.)
NO
Is audio signal (L/R) input to pins [M29/MONITOR_R] [M30/
MONITOR_L] of IC3302? YES Check the line between IC3302 and J506.
(Q507, 508, Q509, D526)
NO
Check IC3302 and its peripheral circuits.