Read Sharp LC-37AD1E (serv.man9) Service Manual online
42
LC-37AD1E
No sound comes out at the time of external input. (Sounds come out at the time of TV broadcast receiving.)
No sound comes out from the headphones.
Check or replace the peripheral circuitry of IC2501.
No sound comes out from the monitor
Perform checking from pins (25) and (24) of
IC2501(DACA L/R) to L.P.F (IC2506), H/P AMP
(IC2502) and audio mute (Q2501) and around
the headphone terminal (J2402).
Is the audio output from the monitor output
set to "Variable"? Are the headphones
connected?
Check the headphone mute circuit.
(Check the peripheral circuitry of D2501,
Q2501 and IC2502.)
Is the audio output from IC2501 (MULTI
SOUND PROCESSOR) normal?
Pins (34) and (33) of IC2501 (SC2 OUT L/R)
No sound comes out from the INPUT1 terminal.
No sound comes out from the INPUT2 and 3 terminals.
Is the audio output from IC2501 (MULTI SOUND
PROCESSOR) normal?
Pins (37) and (36) of IC2501 (SC1 OUT L/R)
Is the audio output from IC1301 (AV SWITCH)
normal?
Pins (43) and (45) of IC1301 (SC1 TV SUB
OUT L/R)
Perform checking from pins (37) and (36) of
IC2501 to pins (3) and (1) of SC1101
(IC2506, Q2517 and Q2516) and check the
audio mute circuit (Q1102 and Q1101).
Perform checking from pins (43) and (45) of
IC1301 to pins (3), (1), (24) and (22) of SC1102
(Q1106, Q1105, Q1111 and Q1110) and check
the audio mute circuit (Q1107, Q1104, Q1112
and Q1109).
Check the headphone plug circuit.
Perform checking from pin (4) of headphone
(J2402) to pin (77) of IC2501.
Perform checking from pins (34) and (33) of
IC2501 to pins (10) and (6) of the monitor
output terminal (J1101-) (IC2507, Q2503,
Q2502, Q1115 and Q1114) and check the
audio mute circuit (Q1116 and Q1117).
No sound comes out at the time of DTV receiving.
Check the display side.
No sound comes out at the time of UHF/VHF receiving.
Is the input signal to pins (59) and (61) of IC1301
(AV SW) normal?
Is the input signal to pin (67) (SOUND IF1)
and pin (69) (SOUND IF2) of IC2501
(MULTI SOUND PROCESSOR) normal?
Perform checking from pins (10) and (9) of
P2503 to pins (59) and (61) of IC1301 (AV
SW).
Is the input signal to pin (67) (SOUND IF1)
and pin (69) (SOUND IF2) of IC2501
(MULTI SOUND PROCESSOR) normal?
Is the I2S_DAOUT signal input normally from pin
(6) of IC2501 (MULTI SOUND PROCESSOR) to
pin (60) (12SDA1) of IC2510?
Is the audio output from IC2501 (MULTI
SOUND PROCESSOR) normal?
Pins (28) and (27) (DAC_M L/R) of IC2504
Is the audio output from pins (7) and (1) of
IC2504 (ACTIV FIL) normal?
Check if the I2S_DAOUT, I2S_CL, I2S_WS
and I2S_DAIN signals are output from IC2501
and input to IC2510 (DSP) normally.
Check IC2501 (MULTI SOUND
PROCESSOR) and the peripheral circuitry.
Check the peripheral circuitry of IC2504
(ACTIV FIL).
Is the SIF output from the tuner normal?
(Pin (21) of TU1101)
Check TU1101 (U/V tuner) and the parts
around it.
No sound comes out at the time of TV broadcast receiving. (Sounds come out at the time of external input.)
No sound comes out at the time of external input and PC input. (Sounds come out at the time of TV broadcast receiving.)
Is the audio input signal to IC1301 (AV
SWITCH) normal?
<INPUT1>
Pins (2) and (4) of IC1301 (L/R VIDEO1)
<INPUT2>
Pins (9) and (11) of IC1301 (L/R VIDEO2)
<INPUT3>
Pins (16) and (18) of IC1301(L/R VIDEO3)
<INPUT4>
Pins (23) and (25) of IC1301(L/R VIDEO4)
<PC SOUND INPUT>
Pins (29) and (31) of IC1301(L/R PC-IN)
Check IC1301 (AV SWITCH) and the
peripheral circuitry.
Check IC2501 (MULTI SOUND
PROCESSOR) and the peripheral circuitry.
Are the audio input circuits of IC1301 (AV
SWITCH) normal?
Perform checking from pins (6) and (2) of SC1101
to pins (2) and (4) (L/R VIDEO1) of IC1301.
Perform checking from pins (6) and (2) of SC1102
to pins (9) and (11) (L/R VIDEO2) of IC1301.
Perform checking from pins (27) and (23) of SC1102
to pins (16) and (18) (L/R VIDEO3) of IC1301.
Perform checking from pins (5) and (7) of J2404 to
pins (23) and (25) (L/R VIDEO4) of IC1301.
Perform checking from pins (2) and (3) of J2403 to
pins (29) and (31) (L/R PC-IN) of IC1301.
Is the audio output signal from IC1301 (AV
SWITCH) normal?
Is the audio input signal to IC2501 (MULTI
SOUND PROCESSOR) normal?
(AVC System)
YES
YES
YES
YES
NO
YES
YES
NO
NO
NO
NO
NO
NO
NO
YES
YES
YES
YES
YES
NO
YES
NO
YES
YES
Click on the first or last page to see other LC-37AD1E (serv.man9) service manuals if exist.