Sharp LC-37AD1E (serv.man9) Service Manual ▷ View online
49
LC-37AD1E
YES
No
YES
YES
YES
No
YES
No
No
No
Noise is caused to the moving picture when
the QS drive is set to ON.
the QS drive is set to ON.
Is OSTEMP.AD on the 3rd page of the
process adjustment mode set to 255?
process adjustment mode set to 255?
Is the harness connected correctly
between the Thermistor PWB and
Inverter-4 PWB?
between the Thermistor PWB and
Inverter-4 PWB?
Is the board-to-board connected
correctly between the Inverter-3 PWB
and Inverter-4 PWB?
correctly between the Inverter-3 PWB
and Inverter-4 PWB?
Is the harness connected correctly
between the Monitor PWB and
Inverter-3 PWB?
between the Monitor PWB and
Inverter-3 PWB?
Is the input voltage on pin (2) of
IC2004 (microprocessor) 5V?
IC2004 (microprocessor) 5V?
TH6301 thermistor
is faulty.
is faulty.
Check IC4701 and
IC4901 and the peripheral
circuitry.
IC4901 and the peripheral
circuitry.
Connect the harness
correctly or replace it.
correctly or replace it.
Connect the board-to-
board securely or replace
it.
board securely or replace
it.
Connect the harness
correctly or replace it.
correctly or replace it.
Pin (2) of IC2004
(microprocessor) is faulty.
(microprocessor) is faulty.
50
LC-37AD1E
YES
No
YES
YES
YES
No
YES
No
No
No
No
Check if the internal/external
switching relay (RY3901)
functions correctly.
switching relay (RY3901)
functions correctly.
Is the output signal from the
1-bit amplifier applied to
P3903?
1-bit amplifier applied to
P3903?
Perform checking around
IC2004, IC3804 and the 1-
bit amplifier.
IC2004, IC3804 and the 1-
bit amplifier.
Are the MUTE circuits
(Q3804 and Q3805)
operating?
(Q3804 and Q3805)
operating?
Is the audio signal applied to
pin (7) (L-IN) and pin (9) (R-
IN) of P3804?
pin (7) (L-IN) and pin (9) (R-
IN) of P3804?
Perform checking
around IC3803 and
IC3808.
around IC3803 and
IC3808.
Check for the AVC
System side for output.
System side for output.
Is the audio signal applied to
pin (13) and pin (20) of
SC2202 on the Monitor PWB?
pin (13) and pin (20) of
SC2202 on the Monitor PWB?
Perform checking around Q2012 and
Q2014 and check the wire between
Monitor PWB and Audio PWB.
Q2014 and check the wire between
Monitor PWB and Audio PWB.
Check if 5V is supplied to the power
regulator circuit (IC3812 and IC3816)
and pin (2) of P3804.
regulator circuit (IC3812 and IC3816)
and pin (2) of P3804.
Is power supplied to each IC
on the AUDIO PWB?
on the AUDIO PWB?
Is the audio signal applied
to pin (13) and pin (15) of
P3803?
to pin (13) and pin (15) of
P3803?
No sound comes out. (Checking with the AVC
System connected)
System connected)
YES
No
No
YES
YES
No
YES
Check the connection of the high-voltage
(pin (2)) wire on the side of the blown
fuse and check that of the counterpart
high-voltage (pin (2)) wire of the
fluorescent lamp on the opposite side.
(pin (2)) wire on the side of the blown
fuse and check that of the counterpart
high-voltage (pin (2)) wire of the
fluorescent lamp on the opposite side.
The backlight does not go on.
Is any of the fuses of
F7501-F7504,
F7551-F7553 and
F7641-F7643
blown?
F7501-F7504,
F7551-F7553 and
F7641-F7643
blown?
Is the control signal applied to
pin (2) (OFL1) and pin (3)
(OFL2) of P7506 and P7616?
pin (2) (OFL1) and pin (3)
(OFL2) of P7506 and P7616?
Is the harness connected correctly
between the Monitor PWB and
Inverter-1 and -3 PWBs?
between the Monitor PWB and
Inverter-1 and -3 PWBs?
Check the peripheral circuitry of
IC4501 of the Monitor PWB and
check the operation of Q7704
and Q7705.
IC4501 of the Monitor PWB and
check the operation of Q7704
and Q7705.
Is power supplied to each
Inverter PWB?
Inverter PWB?
Check the wire connecting the Inverter-1 and -3 PWBs, the
wire connecting the Inverter-2 and -4 PWBs, the board-to-
board between the Inverter-1 and -2, and the board-to-
board between the Inverter-3 and -4.
wire connecting the Inverter-2 and -4 PWBs, the board-to-
board between the Inverter-1 and -2, and the board-to-
board between the Inverter-3 and -4.
Check the 15V output on the
Power PWB.
Power PWB.
Check the inverter
circuit downstream
from the blown fuse.
circuit downstream
from the blown fuse.
Check the counterpart
inverter circuit on the
opposite side.
inverter circuit on the
opposite side.
51
LC-37AD1E
YES
YES
YES
No
Check the input/output
voltage of IC4101.
voltage of IC4101.
Check the performance of Q4101 and Q4112
and check the resistance around IC4102.
and check the resistance around IC4102.
Is the voltage of R4114 about 6V?
The whole screen is whitish (LCD power supply)
Check the power supplies.
Check the power supplies to
SC4101 and SC4102 in particular.
Check the power supplies to
SC4101 and SC4102 in particular.
Remove the FFCs attached to SC4101,
SC4102 and SC4601- SC4604
(because the panel may be broken).
SC4102 and SC4601- SC4604
(because the panel may be broken).
51
LC-37AD1E
YES
YES
YES
No
Check the input/output
voltage of IC4101.
voltage of IC4101.
Check the performance of Q4101 and Q4112
and check the resistance around IC4102.
and check the resistance around IC4102.
Is the voltage of R4114 about 6V?
The whole screen is whitish (LCD power supply)
Check the power supplies.
Check the power supplies to
SC4101 and SC4102 in particular.
Check the power supplies to
SC4101 and SC4102 in particular.
Remove the FFCs attached to SC4101,
SC4102 and SC4601- SC4604
(because the panel may be broken).
SC4102 and SC4601- SC4604
(because the panel may be broken).