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Troubleshooting Guide

DEAD SET
(NO RASTER/NO SOUND)



Check +B voltage at J131
112V(or 118V) 0V


Check the heater elements Check the rectified voltage
of CPT are lighting or not of main power at C817(+)

No 0V

Check/Replace FR423 Check/Replace
F801, DB813, R821, T801

Yes 150~ 380V
Check the voltage at Check the voltage
C430(+) at pin9 of IC802

Lower than 6V
0.1V 8V
Check/Replace
Check/Replace IC430 Check the voltage D810, ZD810, Q810
R430, IC401, D411, FR422 at pin21 of IC501

6~ 8V

0.1V over 0.4V Check/Replace
IC802, D806, D811.
Check/Replace IC501 Check/Replace IC01 Check the secondary
(IC202, IC01T, IC02T: voltage are short
in case of with TXT)
NO PICTURE/NO SOUND

(RASTER OK)
Check the voltage of
TUNER MB(12V)
11.8~ 12.2V


Check/Replace Check the tuning Check/Replace
Tuner condition FR422, D411, IC401




Check the 33V at C416(+)

0V

Check/Replace
R421, ZD404
NO RASTER(SOUND OK)



Check heater elements of
CRT are lighting
No Yes




Check the AC voltage at The screen is Retrace line
H/T pin of CPT SOCKET blinking is visible
on CPT board


6.0~ 6.5Vrms Check replace Check the screen voltage (G2)
IC501 alignment is correct or not
Check/Replace
CPT
Abnormal Normal

0Vrms Readjust White
Check the screen colour
Balance
Check/Replace
FR423, 420
White R/G/B
Check the 180V Check the base voltage
line at C418(+) of Q901-Q903


Abnormal
Check/Replace 12V 4~ 5V
D413
Check/Replace Check/Replace
D901~ D903 R918-920 or
soldering
condition on
CPT board.
NO SOUND(PICTURE OK)



Check the voltage(SMPS 25V)
at pin5 of IC601


Abnormal Normal(20~ 27V)
Check/Replace of Check the voltage at
FR804, D804 pin16 of IC501

10~ 12V
Check the soldering Check/Replace Q508
state around IC601 (TV/AV, TXT switch)


Abnormal Normal
Check/Replace Check the voltage
IC01 at pin 10 of IC501


0V 7~ 9V
Check the voltage
Check/Replace IC430
at pin 5 of IC501



Check whether the
Check/Replace IC601
voltage is swing or not at
pin3 of IC01 when turning
the volume up




Check/Replce IC01
NO COLOR



Check the frequency(4.43/3.58MHz)
at pin 34.35 of IC501


Abnormal Normal

Check/Replace Check the voltage
X501, 502 of PIN27 of IC501.

Below 5V Abnormal
Check/Replace Check whether the voltage is swing
IC501 or not at the pin5 of IC01 according to
changing colour up/down


Not Swing
Check/Replace Check whether R-Y and B-Y are
IC01 out from pin30 and pin31 of IC501


Not Swing
Check/Replace Check whether R-Y and B-Y are
IC501 out from pin9 and pin10 of IC503


No Yes
Check/Replace Check whether R-Y and B-Y are
IC503 out from pin11 and pin12 of IC502


No Yes
Check/Replace Check wheter R/G/B is out from
IC502 pin20, pin19 and pin18 of IC501

No
Check/Replace
IC501
NO TELETEXT




Check the voltage 12V at C403(+)



Abnormal Normal
Check the 12V line Check the voltage of
to be correct C21T(+)


Abnormal 4.8~ 5.2V
Check/Replace Check video signal is
IC04T normal at the pin3 of
IC01T


NO Yes
Check/Replace
Check I2C Bus (SDA, SCL)
Q21T


NO Yes

- Check/Replace Check/Replace X01T
IC01T, IC02T