Sharp LC-37D64U Service Manual page 55

No INPUT-4/5(HDMI) audio
If no video appears, refer to "No external input video (HDMI)
[INPUT-4/5]".
Is the HDMI_MUTE line as specified?
Check Q1301, IC1302 and their peripheral
circuits.
YES
Is there the SPDIF signal (OPT_OUT) output at pin(AP11) of IC8001(CPU)?
Is there the SPDIF signal (OPT_OUT) input at pin(2) of
IC1304(SPDIF_BUFF&MUTE)?
Is there the MUTE signal input at pin(1) of IC1304?
Is there the SPDIF signal input at pin(1) of D1306(OPTICAL
OUTPUT)?
Check the speakers and their peripheral circuits.
No audio signal at Digital Audio Output terminal (Analog sound heard)
NO
YES
YES
YES
YES
No audio at digital broadcast signal reception
Are there the video signal outputs (IF_OUT_P/N) at the pins(19)
and (20) of tuner(TU1101) on the TERMINAL unit?
YES
Are there the video signal outputs at pins(5) and (7) of connec-
tor(SC501) on the TERMINAL unit?
YES
Are there the video signal inputs at pins(5) and (7) of connec-
tor(SC2203) on the MAIN unit?
YES
Are there the video signal inputs at pin(AM33) and (AM34) of
IC8001(CPU)?
YES
Check the IC8001 and its peripheral circuits.
NO Check the line between IC8001 and IC1304.
NO Check the MUTE_A_ALL and ACDET signals, and their periph-
eral circuits.(Q1304, Q1312, D1310, etc.)
NO Check D1306 and its peripheral circuits.
No optical output under the following conditions as per HDMI
requirements.
*Audio contents protected.
*Audio frequency beyond 48kHz.
*Audio bit length beyond 16bits.
6 – 12
LC-32/37D64U
NO
Check the tuner(TU1101) and its periph-
eral circuits.
NO
Check the line between TU1101 and
SC501.
NO
Check the line between SC2203 and
SC501 connectors.
NO
Check the line between IC8001 and
SC2203.(L2204, C2229, etc.)
NO