Sharp LC-19S7E-BK Service Manual page 29

No sound output in all modes?
↓
TEREMINAL UNIT:
Is the audio signal output of pin (84) (DACOUTL0) and pin (85)
(DACOUTR0) of IC U4201 normal?
Is the audio signal output of pin (9) (OUTL) and pin (11) (OUTR) of
IC U6101 normal?
Is audio signal input to pin (5)(LIN), pin (6)(RIN) of IC U6102
(AMP)?
Is MUTE/SHUTDOWN circuit [AMP_MUTE, AMP_STBY] normal?
Is the audio signal output of pin (3,4) (LOUT+) and pin (1,2)
(ROUT+) of CN6101 (AUDIO-CONNECTOR) normal?
Check Speaker Box (right and left) and wire harness.
Does not the sound go out though the picture has come out when UHF/VHF is received?
↓
TEREMINAL UNIT:
Is the SIF signal output from pin (13) of TUNER (TU1101)?
Is the SIF signal sent to pin 54(SIFP) and pin 55(SIFM) of IC
U4201?
Refer to "No sound output in all modes".
The sound is not emitted from the speaker though the picture has come out.
↓
↓YES
↓YES
↓YES
↓YES
↓YES
No sound (during the reception of TV(ANALOG) broadcasting)
↓
↓YES
↓YES
2008-03-14
No sound from external input devices (1)
LC-19S7E-BK LC-26S7E-BK LC-32S7E-BK
NO Check IC U4201 and its peripheral circuits.
NO
Check IC U6101 and its peripheral circuits.
NO
Check the line between IC U6101 and IC U6102.
NO
Check the AMP_MUTE and AMP_STBY. (Q6106, etc.)
NO Check IC U6102 and its peripheral circuits.
NO
Check the tuner and its peripheral circuits. Replace as required.
NO
Check IC U4201 its peripheral circuits.
.
29