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No audio output during UHF/VHF reception

Checklist:
1) Is the volume set to MIN or MUTE on the remote control? ••• Set the desired volume.
2) Are headphones connected to HEADPHONE (J1301)? ••• Disconnect them.
3) Is ANT-CABLE disconnected or connected improperly? ••• Connect it correctly as per the operation manual.

Is the audio signal (L/R) sent from pins (28) and (27) of IC3002 
(VCT)?

Is the audio signal of pins (3) 
and (5) of IC303 (OP-AMP) 
sent properly?

(AV-UNIT)

(TUNER)

Check IC303 or peripheral 
circuits.

Is the audio signal of pin (4) 
of IC301/IC302 (AUDIO-
AMP) sent properly?

Check HEAD-PHONE 
(J1301) or peripheral 
circuits.

Is the audio signal output of 
pins (2) and (4) of P301 
(AUDIO-CONNECTOR) 
normal?

Check SP-BOX (right and 
left) and wire harness.

Check P301 (AUDIO-
CONNECTOR) and 
peripheral circuits.

Is the audio signal (SIF) sent 
from pin (1) of CONNECTOR 
(SC2705)?

Check pin (31) of IC3002 
(VCT) and peripheral 
circuits.

Is the SIF signal (SIF_IN1+) 
sent to pin (31) of IC3002 
(VCT)?

Check whether +5V and +8V 
are supplied to pins (18) and 
(33) of IC3002 respectively.  
Or, check peripheral circuits.

Is the audio signal (SIF) sent 
from pin (12) of IC201 (IF-
DEMOD)?

Check Q203 (AMP) and 
peripheral circuits.

Is the SIF signal sent to pins 
(23) and (24) of IC201 (IF-
DEMOD)?

Check IC201 and peripheral 
circuits.

Is the IF signal sent from pin 
(8) of TUNER (TU201)?

Check FL202 and peripheral 
circuits.

Check whether 33V and 5V 
are supplied to pins (9) and 
(7) of TUNER (TU201) 
respectively. Check SDA/SCL 
and AGC signal.

Replace TUNER (TU201).

No sound from an external 
input device connected to 
EXT1 (SCART1).

No sound from an external 
input device connected to 
EXT2 (SCART2).

No sound from an 
external input device 
connected to EXT3.

No sound from EXT4 
(AUDIO) connecting an 
external input device.

No sound from EXT5 
(AUDIO) connecting an 
external input device.

<EXT1>
Is IN1-L audio signal sent 
from pin (6) of SCART1 
terminal (J1101) to pin 
(14) of IC3002 (VCT)?
Is IN1-R audio signal sent 
from pin (2) of SCART1 
terminal (J1101) to pin 
(13) of IC3002 (VCT)?

<EXT2>
Is IN2-L audio signal sent 
from pin (27) of SCART2 
terminal (J1101) to pin 
(12) of IC3002 (VCT)?
Is IN2-R audio signal sent 
from pin (23) of SCART2 
terminal (J1101) to pin 
(11) of IC3002 (VCT)?

<EXT3>
Is IN3-L audio signal 
sent from pin (3) of 
J1201 terminal to pin 
(16) of IC3002?
Is IN3-R audio signal 
sent from pin (5) of 
J1201 terminal to pin 
(15) of IC3002?

Is the audio signal 
properly sent from pins 
(28) and (27) of IC3002?

Check IC3002 or 
peripheral circuits.

Is the audio signal of 
pins (7) and (1) of IC303 
(OP-AMP) sent properly?

Check IC303 or 
peripheral circuits.

<EXT4>
Is D-SUB-L audio signal 
sent from J2702 to pin 
(15) of IC2704?
Is D-SUB-R audio signal 
sent from J2702 to pin 
(2) of IC2704?

Is D-SUB-L audio signal 
sent to pin (10) of 
IC3002?
Is D-SUB-R audio signal 
sent to pin (9) of 
IC3002?

<EXT5>
Is HDMI-L audio signal 
sent from J2701 to pin 
(14) of IC2704?
Is HDMI-R audio signal 
sent from J2701 to pin 
(5) of IC2704?

Check pins (6) and 
(2) of SCART1 and 
connection to an 
external input 
device.

Check pins (27) and 
(23) of SCART2 and 
connection to an 
external input 
device.

Check pins 3 
(J1201) and 5 
(J1201) of EXT3 
and connection to 
an external input 
device.

Is HDMI-L audio 
signal sent to pin 
(10) of IC3002?
Is HDMI-R audio 
signal sent to pin (9) 
of IC3002?

Is the audio output 
signal of pins (13) and 
(16) of IC302/IC301 
(MAIN-AMP) normal?

Check IC302/IC301 
(MAIN-AMP),
HEADPHONE and 
peripheral circuits.

Check CONNECTOR 
(P301) and SP-BOX 
(right and left).

Check output of pins 
(13) and (3) of 
IC2704 and 
peripheral circuits.

Check that Option-
HDMI Setup-Audio 
select is set to 
"Analog".

Check audio input signal of pin (31) of IC3002 (VCT), pins (18) 
and (33) of the power line, pins (84) and (83) of I2C-LINE, and 
peripheral circuits.

No audio output from the 
headphones

No audio output from EXT1 
(SCART) terminal.

Is there audio output on pins 
(2) and (3) of the headphone 
terminal (J1301)?

Checklist:
1) Is the MUTE button on the remote control set to ON? ••• Set to OFF.
2) Check the connection to external devices. ••• Is there any improper connection?

Is audio input/output signal of 
pins (3) and (5)/(1) and (7) of 
IC303 (OP-AMP) normal?

Is audio output signal (SPK-
OUT L/R) properly sent from 
pins (28) and (27) of IC3002 
(VCT)?

Check the connection to 
EXT1 (J1101) and external 
devices.

Check the connection to 
EXT2 (J1101) and external 
devices.

Is S-MUTE-LINE [IC1710 (pin 
21)] or S2-MUTE-LINE 
[IC3003 (pin 26)] at H?
(Check Q1102/Q1101 
operation.)

Is audio signal sent from pins 
(22) and (21) of IC3002?

Check the audio signal 
output line from pins (22) and 
(21) of IC3002 to 
Q1103/Q1104/Q1201/Q1202

Check the connection to 
AUDIO OUTPUT terminal 
(J1201) and external devices.

Is S-MUTE-LINE [IC1710 (pin 
21)] at H?
(Check Q1204/Q1203 
operation.)

Is audio signal sent to pins 
(3) and (1) of EXT1 (J1101)?

Is S-MUTE-LINE [IC1710 
(pin 21)] at H?
(Check Q1106/Q1105 
operation.)

Is audio signal sent from 
pins (24) and (23) of 
IC3002?

Check the audio signal 
output line from pins (24) 
and (23) of IC3002 to pins 
(3) and (1) of EXT1.

Check the power supply 8/5 
V pins (18) and (33) of 
IC3002 and peripheral 
circuits.

Is audio signal sent to pins 
(24) and (22) of EXT2 
(J1101)?

Is audio signal sent to pins 
(13) and (15) [L/R (white) 
(red)] of AUDIO OUTPUT 
terminal (J1201)?

No audio output from EXT2 
(SCART) terminal.

No audio output from AUDIO 
OUTPUT terminal.

No picture appears on LCD during the tuner (U/V) reception.

Checklist:
1) Is "INPUT SOURCE" button        on the remote control set up correctly? ••• See the operation manual and set "INPUT SOURCE" to "TV".
2) Is MENU-PICTURE-Contrast/Brightness set to "MIN"? ••• Set it to an appropriate level.
3) Is ANT-CABLE disconnected or connected improperly? ••• Connect it correctly as per the operation manual.

Is level of pins (4) and (5) of 
tuner (TU201) and pins (10) 
and (11) of IC201 (IF-
DEMOD) at H?

These are communications 
lines for control (I2C). Follow 
the path and check whether 
they are forced to L 
(PULL_DOWN).

Is the video signal (IF) sent 
from pin (8) of tuner 
(TU201)?

Check the tuner (TU201) 
and peripheral circuits.

Is video signal sent from pin 
(17) of IC201 (IF-DEMOD)?

Check FL201 (SAW-FIL), 
IC201 and peripheral 
circuits.

Is the video signal VIN1 
(ATUNER-CVBS) sent to pin 
(191) of IC3002 (VCT)?

Check IC201 (IF-DEMOD), 
CONNECTOR 
(P201/SC2705) and 
peripheral circuits.

Is LVDS video signal (LVDS_0N/0P-3N/3P) sent to pins 
(141)/(140) - (129)/(128) of IC3002 (VCTP), and is CLK signal 
(LVDS_CN/CP) sent to pins (132)/(131)?

Check pins (192)/(170)/(133) of BU3.3V line of IC3002 (VCTP), 
pins (185)/(169)/(142) of 1.8V line and peripheral circuits.

Is LVDS video signal (LVDS_0N/0P-3N/3P) sent to pins (12)/(13) - 
(24)/(25) of CONNECTOR CN1 of LCD-CONT-UNIT, and is CLK 
signal (LVDS_CN/CP) sent to pins (21)/(22)?

Check CONNECTOR (P2305, CN1) and HARNESSWIRE (LV).

Is power (LCD5V) supplied to pins (2) – (5) of CONNECTOR CN1 
in LCD-CONT-UNIT?

Replace LCD-CONT-UNIT.

Is LCD5V supplied to pins (31) – (28) of CONNECTOR (P2305)?
Check Harness Wire (LV).