Sharp LC-40LE820E, Service Manual

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LC-40/46/52LE820E, LC-40/46LU820E
7 – 2
The sound is not emitted from the Speaker & Woofer though the picture has come out.
No sound output in all modes?
YES
Is the signal output from pins (F30/AOLRCK), (F28/AOBCK)
(G28/AOSDATA0) of IC3302 (Digital AV decode & Main CPU)? NO Check IC3302 and its peripheral circuits.
YES
Is the signal sent to pins (7), (8), (9) of IC2701 (DSP)? NO Check the line between IC3302 and IC2701.
YES
Is the signal output from pins (43/AOBCKL), (44/AMP_LRCLK),
(45/AMP_DATA_LR), (46/AMP_DATA_SW), (47/AMP_MCLK) of
IC2701? NO Check IC2701 and its peripheral circuits.
YES
In the case that the sound is not emitted from the Speaker, refer
to (A)
In the case that the sound is not emitted from the Woofer, refer to
(B)
(B)
(A)
Is the signal sent to pins (5), (6), (7), (8) of IC2703
(SP_AMP)? NO Check the line between IC2701 and IC2703.
YES
Is the audio signal output from pins (28/OUTML), (30/
OUTPL), (12/OUTPR), (14/OUTMR) of IC2703? NO Check IC2703 and its peripheral circuits.
YES
Is the audio signal input to pins (1, 2/L-ch), (3, 4/R-ch) of
IC2703? NO P2701 terminal and the peripheral circuit (L/C filter) are checked.
YES
Check Speaker (right and left) and wire harness.
Is the signal sent to pins (5), (6), (7), (8) of IC2702
(Woofer_AMP)? NO Check the line between IC2701 and IC2702.
YES
Is the audio signal output from pins (28/OUTML), (30/OUTPL),
(12/OUTPR), (14/OUTMR) of IC2702? NO Check IC2702 and its peripheral circuits.
YES
Is the audio signal input to pins (1/SUB(+)), (2/SUB(-)) of
IC2702? NO P2702 terminal and the peripheral circuit (L/C filter) are checked.
YES
Check Woofer (right and left) and wire harness.