Sharp LC40E67U - LC - 40" LCD TV, Service Manual

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LC-40E67U/LC-40E77U
6 – 8
No audio (1)-1
INPUT-1 No audio. INPUT-2 No audio.
Is INPUT-1 selected on the input select menu screen? Is INPUT-2 selected on the input select menu screen?
YES
NO
YES
NO
Refer to “: No external input video [INPUT-1]”. Refer to “: No external input video [INPUT-2]”
Is the audio output selected for “VARIABLE” on the menu screen? Is the audio output selected for “VARIABLE” on the menu screen?
YES
NO
YES
NO
Set the audio output to “FIXED”. Set the audio output to “FIXED”.
Does the audio signal come from pins (4) (L) and (2) (R) of input
terminal (J502) to pins (12) (L) and (1) (R) of IC503 (AUDIO
SWITCH)? Does the audio signal come from pins (4) (L) and (2) (R) of input terminal
(J505) to pins (15) (L) and (2) (R) of IC503 (AUDIO SWITCH)?
YES
NO
YES
NO
Check the line between J502 and IC503. Check the line between J505 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)? 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
YES
NO
Check IC503/IC8001 and its peripheral circuits
(IC502, Q509, Q510,etc).
Check the line between IC503 and IC8001. 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 circuits.