Sharp Aquos LC 32D50U, Service Manual

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LC-32D50U
6 – 2
No audio output during UHF/VHF reception
Is Video output during UHF/VHF reception normal?
NO Check the tuner and RF-SW (UNT 501)
YES
Is SIF output from the tuner (TU1101_Pin3) normal? NO Check the tuner and peripheral circuits.
YES
Is input signal fed to pin 21 (SOUNDIF 1) of IC1401 (SIF Demod-
ulator) normal? NO Check the filter circuits (Q1144 and Q1102-3) and peripheral cir-
cuits.
YES
Are audio signals from pins 29 and 30 (SC2_OUTL/R) of IC1401
to pins 51 and 52 of IC1403 (CODEC) normal? NO Check between pins 29 and 30 (SC2_OUTL/R) of IC1401 and
pins 51 and 52 of IC1403 (CODEC).
YES
Are audio outputs (A-OUT_L/R) of pins 38 and 39 of IC1403 nor-
mal? NO Are the LRCK, BICK, SDTO and SDTI signals sent from IC1403
to IC1406 (DSP) normally?
YES
YES
Check IC1403 and peripheral circuits.
Is audio input from pins 38 and 39 of IC1403 to pins 11 and 15 of
IC2701(STEREO_AMP) normal? NO Check the circuits between pins 38 and 39 of IC1403 and pins 11
and 15 of IC2701. (MUTE circuits: Q1306-8)
YES
Is audio output from IC2701 normal? NO Check IC2701 and peripheral circuits.
YES
Is the speaker switching circuit (T2701)
YES
Check the connector (P2703) of AV_UNIT and around the speak-
ers.
No monitor audio output
Is monitor audio output set to "Variable"?
YES Reset monitor audio output to "Fixed".
NO
Are audio output pins 40 and 41 of IC1403 (CODEC) normal? NO Check IC1403 and peripheral circuits.
YES
Are audio output pins 7 and 1 of IC1407 (Buffer_AMP) normal? NO Check IC1407 and peripheral circuits.
YES
Check between IC1407 and MONITOR OUTPUT terminal (pins
10 and 16 of J502).