Sharp LC-46D65E/RU Service Manual page 38

LC-46D65E/RU
No audio signal output from EXT1/EXT2 terminal.
Is there a audio output signal in pins (3/L-ch) and (1/R-ch) of
EXT1 (SC502)?
Is there a audio output signal in pins (3/L-ch) and (1/R-ch) of
EXT2 (SC501)?
<EXT1>
Is SC-MUTE [pin (67) of IC9101 (CPLD)] at H?
<EXT2>
Is SC2-MUTE [pin (65) of IC9101 (CPLD)] at H?
<EXT1>
Is there a audio output signal in pins (39/SC1_OUT_L) and (38/
SC1_OUT_R) of IC503(AV_SW)?
<EXT2>
Is there a audio output signal in pins (37/SC2_OUT_L) and (36/
SC2_OUT_R) of IC503 (AV_SW)?
Check IC503 and its peripheral circuits.
No audio signal output from AUDIO_OUTPUT terminal.
Is audio signal (L/R) output to pins (2, 4) of AUDIO_OUTPUT ter-
minal (J503)?
MONITOR_MUTE signal [Pin (23) of IC503 (AV_SW.)] or MUTE-
A_ALL signal [Pin (21) of IC2003] will be "H"?
Is audio signal (L/R) output to pins (5, 6) of IC1302 (DSP)?
Check IC1302 and its peripheral circuits.
The audio signal is not output (1)
NO
NO
NO
The audio signal is not output (2)
NO
NO
NO
YES Check the setting of an external input device that connects with
EXT1.
YES Check the setting of an external input device that connects with
EXT2.
YES Check the peripheral circuits of IC9101 and SC-MUTE.
(Q503, Q505, etc.)
YES Check the peripheral circuits of IC9101 and SC2-MUTE.
(Q502, Q504, etc.)
YES Check the line between IC503 and SC502.
YES Check the line between IC503 and SC501.
YES Check the connection to AUDIO_OUTPUT terminal and external
input devices.
YES Check the peripheral circuits of IC503 and MUTE-A_ALL_LINE.
(D534, etc.)
YES Check the line between IC1302 and J503.
(Q510, Q511, Q512, Q513, etc.)
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