Sharp AQUOS LC-42D64U, Service Manual

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LC-42/46/52D64U
6 – 17
No audio signal at Digital Audio Output terminal (Analog sound heard)
No INPUT-4/5/6(HDMI) audio No audio at digital broadcast signal reception
If no video appears, refer to “No external input video (HDMI)
[INPUT-4/5/6]”. Are there the video signal outputs (IF_OUT_P/N) at the pins(19) and
(20) of tuner(TU1101) on the TERMINAL unit?
YES
NO
Is the HDMI_MUTE line as specified? Check the tuner(TU1101) and its peripheral circuits.
YES
NO
Check Q1301, IC1302 and their peripheral circuits. Are there the video signal outputs (IF_OUT_P/N) at the pins(19) and
(20) of tuner(TU1101) on the TERMINAL unit?
YES
NO
Does the HDMI_SPDIF signal come from pin (78) of
IC1502(HDMI-Rx) to pins(AM11) and (AN11) of IC8001(CPU)? Check the tuner(TU1101) and its peripheral circuits.
YES
NO
Check the line between IC1502 and IC8001, and
their peripheral circuits. Are there the video signal outputs at pins(70) and (72) of connec-
tor(SC501) on the TERMINAL unit?
YES
NO
Check the line between TU1101 and SC501.
Are there the video signal inputs at pins(70) and (72) of connec-
tor(SC2203) on the MAIN unit?
YES
NO
Check the line between SC2203 and SC501 connec-
tors.
Are there the video signal inputs at pin(AM33) and (AM34) of
IC8001(CPU)?
YES
NO
Check the line between IC8001 and SC2203 (L2204,
C2229, etc.).
Is there the SPDIF signal (OPT_OUT) output at pin(AP11) of IC8001(CPU)?
YES
NO
Check the IC8001 and its peripheral circuits.
Is there the SPDIF signal (OPT_OUT) input at pin(2) of
IC1304(SPDIF_BUFF&MUTE)? NO Check the line between IC8001 and IC1304.
YES
Is there the MUTE signal input at pin(1) of IC1304? NO Check the MUTE_A_ALL and ACDET signals, and their peripheral
circuits(Q1304, Q1312, D1310, etc.).
YES
Is there the SPDIF signal input at pin(1) of D1306(OPTICAL OUT-
PUT)? NO Check D1306 and its peripheral circuits.
YES
No optical output under the following conditions as per HDMI require-
ments.
*Audio contents protected.
*Audio frequency beyond 48kHz.
*Audio bit length beyond 16bits.
Check the speakers and their peripheral circuits.