Read Sharp LC-52XL1E (serv.man3) Service Manual online
LC-46XL1E/RU, LC-52XL1E/RU
4 – 1
LC46XL1E
Service Manual
CHAPTER 4.
TROUBLESHOOTING TABLE
[1] TROUBLESHOOTING TABLE
Power switched on but no power supplied.
Are the power cord and internal harnesses correctly con-
nected?
NO
Reconnect the cables correctly and switch on the power again.
YES
Does F701 function?
NO
Replace F701 and switch on the power again. Does the fuse blow
out?
out?
YES
NO
YES
Is there a voltage of about 5V at the BU5V output [between pins (20) (+) and (22) (-) of PA]?
YES
NO
Replace R790, D742,
IC702, R780 and R781.
IC702, R780 and R781.
NO
Is the voltage at C790
higher than 8V?
higher than 8V?
YES
Are there voltages of about 13V, 24V and 35V at the UR13V,
S29V and UR35V outputs, respectively?
S29V and UR35V outputs, respectively?
NO
Check D708, Q727, Q726,
R830, R829, D762, D763,
Q741, R824, R825, IC704,
R826, R827 and R828.
R830, R829, D762, D763,
Q741, R824, R825, IC704,
R826, R827 and R828.
Replace Q705, D715,
IC701, R726 and R721.
IC701, R726 and R721.
YES
Is the relay activated clicking?
NO
Check Q706, Q741, D707, D729 and R776.
YES
Is there a voltage of about 12V at UR12V [between pins (1)
(+) and (3) (-) of PL]?
(+) and (3) (-) of PL]?
NO
Check Q731, Q742, Q732, D767, D766, R843, R844 and C799.
YES
Is there a voltage of about 380V at C726?
NO
Check Q705, D715, IC701, R726 and R721.
YES
Is there a voltage of about 60V at the INV60V output
[between pins (1) (+) and (3) (-) of LA]?
[between pins (1) (+) and (3) (-) of LA]?
NO
Check Z1, Q707, Q708, Q716 and L706.
YES
Is there a voltage of about 10V at the INV10V output
[between pins (5) (+) and (3) (-) of LA]?
[between pins (5) (+) and (3) (-) of LA]?
NO
Check IC705, R832, R833, R834 and C813.
LC-46XL1E/RU, LC-52XL1E/RU
4 – 2
No sound (1) (during the reception of TV broadcasting)
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.
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 IC3701 (MSP)?
sent from pins (28) and
(27) of IC3701 (MSP)?
NO
Is the SIF signal
(ANA_IN1+) sent to pin
(67) of IC3701 (MSP)?
(ANA_IN1+) sent to pin
(67) of IC3701 (MSP)?
YES
Check whether +5V and
+8V are supplied to pins
(12) and (39) of IC3701
respectively. Or, check
peripheral circuits.
+8V are supplied to pins
(12) and (39) of IC3701
respectively. Or, check
peripheral circuits.
(AV-UNIT)
YES
NO
Is the audio signal of pins
(3) and (5) of IC303 (OP-
AMP) sent properly?
(3) and (5) of IC303 (OP-
AMP) sent properly?
NO
Check SC2704 and P1201
or peripheral circuits.
Is the S-MUTE signal “L”?
or peripheral circuits.
Is the S-MUTE signal “L”?
Is the audio signal (SIF)
sent from pin (1) of CON-
NECTOR (SC2705)?
sent from pin (1) of CON-
NECTOR (SC2705)?
YES
Check pin (67) of IC3701
(MSP) and peripheral cir-
cuits.
(MSP) and peripheral cir-
cuits.
YES
(TUNER)
NO
Is the audio signal of pin
(4) of IC301/IC302
(AUDIO-AMP) sent prop-
erly?
(4) of IC301/IC302
(AUDIO-AMP) sent prop-
erly?
NO
Check HEAD-PHONE
(J1301) or peripheral
circuits.
(J1301) or peripheral
circuits.
Is the audio signal (SIF)
sent from pin (12) of IC201
(IF-DEMOD)?
sent from pin (12) of IC201
(IF-DEMOD)?
YES
Check CONNECTOR
(P201) and peripheral cir-
cuits.
(P201) and peripheral cir-
cuits.
YES
NO
Is the audio signal output
of pins (2) and (4) of P301
(AUDIO-CONNECTOR)
normal?
of pins (2) and (4) of P301
(AUDIO-CONNECTOR)
normal?
NO
Check P301 (AUDIO-
CONNECTOR) and
peripheral circuits.
CONNECTOR) and
peripheral circuits.
Is the SIF signal sent to
pins (23) and (24) of
IC201 (IF-DEMOD)?
pins (23) and (24) of
IC201 (IF-DEMOD)?
YES
Confirm whether +5V is
supplied to IC201.
Or, please check the
peripheral circuit.
supplied to IC201.
Or, please check the
peripheral circuit.
YES
NO
Check SP-BOX (right and
left) and wire harness.
left) and wire harness.
Is the IF signal sent from
pin (17) of TUNER
(TU201)?
pin (17) of TUNER
(TU201)?
YES
Check soldering the termi-
nal and peripheral circuits.
nal and peripheral circuits.
NO
Check whether 5V
(CONT) and 5V are sup-
plied to pins (1) and (2) of
TUNER (TU201) respec-
tively.
Check SDA/SCL and AGC
signal.
(CONT) and 5V are sup-
plied to pins (1) and (2) of
TUNER (TU201) respec-
tively.
Check SDA/SCL and AGC
signal.
YES
Replace TUNER (TU201).
LC-46XL1E/RU, LC-52XL1E/RU
4 – 3
No sound from external input devices (2) -1
No sound from an external input
device connected to EXT1
(SCART1).
device connected to EXT1
(SCART1).
No sound from an external
input device connected to
EXT2 (SCART2).
input device connected to
EXT2 (SCART2).
No sound from an external
input device connected to
EXT3.
input device connected to
EXT3.
<EXT1>
Is IN1-L audio signal sent from
pin (6) of SCART1 terminal
(J1101) to pin (53) of IC3701
(MSP)?
Is IN1-R audio signal sent from
pin (2) of SCART1 terminal
(J1101) to pin (54) of IC3701
(MSP)?
Is IN1-L audio signal sent from
pin (6) of SCART1 terminal
(J1101) to pin (53) of IC3701
(MSP)?
Is IN1-R audio signal sent from
pin (2) of SCART1 terminal
(J1101) to pin (54) of IC3701
(MSP)?
YES
<EXT2>
Is IN2-L audio signal sent
from pin (27) of SCART2 ter-
minal (J1101) to pin (56) of
IC3701 (MSP)?
Is IN2-R audio signal sent
from pin (23) of SCART2 ter-
minal (J1101) to pin (57) of
IC3701 (MSP)?
Is IN2-L audio signal sent
from pin (27) of SCART2 ter-
minal (J1101) to pin (56) of
IC3701 (MSP)?
Is IN2-R audio signal sent
from pin (23) of SCART2 ter-
minal (J1101) to pin (57) of
IC3701 (MSP)?
YES
<EXT3>
Is IN3-L audio signal sent from
pin (3) of J1201 terminal to pin
(47) of IC3701?
Is IN3-R audio signal sent from
pin (5) of J1201 terminal to pin
(48) of IC3701?
Is IN3-L audio signal sent from
pin (3) of J1201 terminal to pin
(47) of IC3701?
Is IN3-R audio signal sent from
pin (5) of J1201 terminal to pin
(48) of IC3701?
NO
NO
NO
Check pins (6) and (2) of
SCART1 and connection to an
external input device.
SCART1 and connection to an
external input device.
Check pins (27) and (23) of
SCART2 and connection to
an external input device.
SCART2 and connection to
an external input device.
Check pins (3) and (5) of EXT3
(J1201) and connection to an
external input device.
(J1201) and connection to an
external input device.
Is the audio signal properly sent from pins (28) and (27) of IC3701?
NO
YES
Check IC3701 or peripheral circuits.
Is the audio signal of pins (1)
and (7) of IC303 (OP-AMP)
sent properly?
and (7) of IC303 (OP-AMP)
sent properly?
NO
Check IC303 or peripheral circuits.
YES
Is the audio output signal of
pins (13) and (16) of IC302/
IC301 (MAIN-AMP) normal?
pins (13) and (16) of IC302/
IC301 (MAIN-AMP) normal?
NO
Check IC302/IC301 (MAIN-AMP),
HEADPHONE and peripheral circuits.
HEADPHONE and peripheral circuits.
YES
Check CONNECTOR (P301)
and SP-BOX (right and left).
and SP-BOX (right and left).
LC-46XL1E/RU, LC-52XL1E/RU
4 – 4
No sound from external input devices (2) -2
No sound from EXT4 (AUDIO) connect-
ing an external input device.
ing an external input device.
No sound from EXT5 (AUDIO) connect-
ing an external input device.
ing an external input device.
<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 from J2702
to pin (15) of IC2704?
Is D-SUB-R audio signal sent from J2702
to pin (2) of IC2704?
<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?
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?
YES
YES
Is D-SUB-L audio signal sent to pin (50)
of IC3701?
Is D-SUB-R audio signal sent to pin (51)
of IC3701?
of IC3701?
Is D-SUB-R audio signal sent to pin (51)
of IC3701?
Is HDMI-L audio signal sent to pin (50) of
IC3701?
Is HDMI-R audio signal sent to pin (51) of
IC3701?
IC3701?
Is HDMI-R audio signal sent to pin (51) of
IC3701?
NO
Check output of pins (13) and (3) of
IC2704 and peripheral circuits.
IC2704 and peripheral circuits.
YES
YES
Is the audio signal properly sent from pins (28) and (27) of IC3701?
NO
Check IC3701 or peripheral circuits.
YES
Is the audio signal of pins (1) and (7) of
IC303 (OP-AMP) sent properly?
IC303 (OP-AMP) sent properly?
NO
Check IC303 or peripheral circuits.
YES
Is the audio output signal of pins (13) and
(16) of IC302/IC301 (MAIN-AMP) nor-
mal?
(16) of IC302/IC301 (MAIN-AMP) nor-
mal?
NO
Check IC302/IC301 (MAIN-AMP),
HEADPHONE and peripheral circuits.
HEADPHONE and peripheral circuits.
YES
Check CONNECTOR(P301) and
SP-BOX (right and left).
SP-BOX (right and left).