Sharp LC32SB27U Service Manual - Page 57

IC503 to pins B2 L and A1 R of IC8001 CPU?

Page 57 highlights

No audio (1)-2 LC-32D47U/LC-32SB27U/LC-C3237U INPUT-3 No audio. Is INPUT-3 selected on the input select menu screen? NO Refer to ": No external input video [INPUT-3]". YES Is the audio output selected for "VARIABLE" on the menu screen? NO Set the audio output to "FIXED". YES Does the audio signal come from pins (5) (L) and (4) (R) of input terminal (J501) to pins (14) (L) and (5) (R) of IC503 (AUDIO SWITCH)? NO Check the line between J501 and IC503. YES Does the audio signal come from pins (13) (L) and (3) (R) of IC503 to pins (B2) (L) and (A1) (R) of IC8001 (CPU)? NO YES Check IC503/IC8001 and its peripheral circuits (IC502, Q509, Q510,etc). Check the line between IC503 and IC8001. Does the audio signal come from pins (C4/A3) (SPOUT_L/R) of IC8001 (CPU) to pins (3) (INLP), and (7) (INRP) of IC2701 (AMP)? YES Is the audio output from IC2701 as specified? NO Check the line between IC8001 and IC2701, and their peripheral circuits (Q1306/Q1307, AMP_MUTE line, etc). NO Check IC2701 and its peripheral circuits. YES Check the connector (P2701), speakers and their peripheral circuits. 6 - 7

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LC-32D47U/LC-32SB27U/LC-C3237U
6 – 7
No audio (1)-2
INPUT-3 No audio.
Is INPUT-3 selected on the input select menu screen?
YES
NO
Refer to “: No external input video [INPUT-3]”.
Is the audio output selected for “VARIABLE” on the menu
screen?
YES
NO
Set the audio output to “FIXED”.
Does the audio signal come from pins (5) (L) and (4) (R) of input
terminal (J501) to pins (14) (L) and (5) (R) of IC503 (AUDIO
SWITCH)?
YES
NO
Check the line between J501 and IC503.
Does the audio signal come from pins (13) (L) and (3) (R) of
IC503 to pins (B2) (L) and (A1) (R) of IC8001 (CPU)?
YES
NO
Check IC503/IC8001 and its peripheral circuits
(IC502, Q509, Q510,etc).
Check the line between IC503 and IC8001.
Does the audio signal come from pins (C4/A3) (SPOUT_L/R) of
IC8001 (CPU) to pins (3) (INLP), and (7) (INRP) of IC2701
(AMP)?
NO
Check the line between IC8001 and IC2701, and their peripheral
circuits (Q1306/Q1307, AMP_MUTE line, etc).
YES
Is the audio output from IC2701 as specified?
NO
Check IC2701 and its peripheral circuits.
YES
Check the connector (P2701), speakers and their peripheral cir-
cuits.