Sharp Aquos LC-30HV4U, Service Manual

Page: 61 / 254

61
LC-30HV4U
LC-30HV4D
No sound (1) No sound (2) No image (1)
No sound is heard from the speak
er in all modes
.
Chec
k audio circuits of the Displa
y.
Is the monitor audio output set to "V
ar
iab
le"? or
Is the headphone connected?
Are the audio signal outputs of IC2501 (m
ulti-
sound processor) in order? Pins (36) and (37) of IC2501 (SC1 OUT L/R).
Chec
k IC2501 (m
ulti-sound processor) and its
per
ipher
al circuits
.
Chec
k lines and de
vices betw
een pins (36), (37)
of IC2501 and pins (1), (3) of the A
V
unit
connector (P2502).
(Q2504-5, Q2507 and
Q2508)
Set the monitor audio output to "Fix
ed".
Remo
v
e
the headphone
.
The speak
er gener
ates no sound when audio signals are inputted from an e
xter
nal de
vice or a PC
.
Chec
k IC1301 (A s
witch) and its per
ipher
als
.
Are the audio outputs of IC1301 (A
V s
w
itch) in
order? Pins (52) and (54) of IC1301 (TV MAIN OUT L/R)
Are the audio signal inputs of IC1301 (A
V
s
witch) in order?
Input 1:
pins (2) and (4) of IC1301
Input 2:
pins (9) and (11) of IC1301
Input 3:
pins (16) and (18) of IC1301
Input 4 (F
ront:J2404):
pins (23) and (25) of
IC1301 PC input (J2403):
pins (29) and (31) of IC1301
Are the audio signal input circuits of IC1301 (A
V
s
witch) in order?
Input 1:
Betw
een pins (5), (14) of J1103 and pins
(2), (4) of IC1301 Input 2:
Betw
een pins (2), (11) of J1103 and pins
(9), (11) of IC1301 Input 3:
Betw
een pins (5), (14) of J1104 and pins
(16), (18) of IC1301 Input 4:
Betw
een pins (5), (7) of J2404 and pins
(23), (25) of IC1301 PC input:
Betw
een J2403 and pins (29), (31) of
IC1301 Are the audio inputs of IC2501 (m
ulti-sound
processor) in order? Pins (56) and (57) of IC2501 (SCI IN1 L/R)
YES
NO
YES YES
YES
NO
NO
NO
No monitor audio output or abnor
mal audio
The audio le
v
el is abnor
mal:
Is the monitor audio output set correctly? "V
ar
iab
le" or "Fix
ed"
YES
No sound at all: Are the audio outputs of IC2501 (Multi-sound processor) in order? Pins (34) and (33) (SC2 OUT L/R) of IC2501
Chec
k lines and de
vices betw
een pins (34), (33)
of IC2501 and the monitor output (J1101).
Also
chec
k the audio m
ute circuit.
(Q2502-3 and Q1102-3)
Chec
k per
ipher
als of the SR unit DISPLA
Y
OUTPUT 2 ter
minal (SC6000).
YES
Are audio signals applied to the A
V
unit
connectors (pins (1) and (3) of P2502)?
YES
The speak
er gener
ates no sound when
TV signal is receiv
ed.
Are the tuner audio inputs of IC2501 (m
ulti-sound
processor) in order? Pin (67) (sound IF1) of IC2501 Pin (69) (sound IF2) of IC2501
Is the audio signal applied to pin (15) of tuner (TU1101/TU1102) output?
Chec
k B
.P
.F
. of SIF1 and SIF2.
(Q1102, Q1105-6, Q1104 and Q1114-5)
Chec
k IC2501 (m
ulti-sound processor) and its
per
ipher
al circuits
.
YES YES
NO NO
Chec
k
TU1101/1102 (U/V tuner) and its per
ipher
als
.
No
VIDEO image (2) on INPUT2
Has "INPUT2" been selected on the Input Select screen?
No
VIDEO image on INPUT1
Has "INPUT1" been selected on the Input Select screen? Is video signal applied to pin (1) (composite video signal input)? Are
Y and C signals applied to pins (3) and (5)
(S video signal input) respectiv
ely?
Are video signals applied to input ter
minal of
IC1301 (A
V SW)?
Chec
k lines and de
vices betw
een pin (23) of
J1103 (INPUT1) and pin (1) of IC1301. Chec
k lines and de
vices betw
een pins (9)/(10)
of SC1101 (INPUT1) and pins (3)/(5) of IC1301.
Select "INPUT1" on the Input Select screen.
NO
Select "INPUT2" on the Input Select screen.
NO YES
NO NO
YES YES
Is video signal applied to pin (8) (composite video signal input)? Are
Y and C signals applied to pins (10) and (12)
(S video signal input) respectiv
ely?
Are video signals applied to input ter
minal of
IC1301 (A
V SW)?
Chec
k lines and de
vices betw
een pin (20) of
J1103 (INPUT2) and pin (8) of IC1301. Chec
k lines and de
vices betw
een pins (3)/(4) of
SC1101 (INPUT2) and pins (10)/(12) of IC1301.
NO NO
YES YES
(A)
(B)
•
AVC System