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TROUBLESHOOTING
NO RASTER
Check +B voltage at
E18
Normal 110Vdc 0V
Is the voltage at pin12, Check the voltage of 110Vdc
37 of IC501 8V? C821
No
Check the voltage 8V Check/Replace R410
Line.
Yes Check/Replace D816,
D821, IC841, D824 Open
Check Fuse of AC line
Does the square
waveform from pin40 of Check/Replace Fuse,
IC501 appear? OK OK
No D801~804, TH801
Check I2C BUS lines
Check/Replace IC501 Yes Check the voltage of 0V
(SDA, SCL)
C806
Is the waveform of
No collector of Q401 normal? Check/Replace
254-380V
D801~804, R801
Check/Replace FR802,
Yes
D817, Q401, Q403, T451 Lower than 18V
Check the voltage of
pin4 of IC803
Is the waveform of
No collector of Q402 normal? Check/Replace
D805~806, IC803,
IC801
Check/Replace Q402,
D403~4, C415,
Yes Check/Replace IC841,
C409~410
IC843, D816, D815
Check the 8V, 5V lines
are shorted.
Check/Replace T406
Check/Replace 0V Check the voltage of
D808~811, T803 C827
10~14Vdc
Check/Replace Q104,
Q802, RL801, IC842
NO SOUND
(PICTURE OK)
(No NICAM or FM Sound)
(No AM Sound)
NO Check whether Sound Incorrect
Check the Audio signal of system of MENU OSD is
pin25 of IC604 normal correct or not
Yes Correct Set correct Sound system
Check/Replace IC604
Yes NO
Check the Audio signal of Is the SIF signal of pin24
pin44 of ICN01 normal of IC604 normal
NO Check/Replace IC101
Yes
NO
Are the Audio signal of
Check AM line
pin24, 25 of ICN01 normal?
Check/Replace XN01,
Yes ICN01
NO
Are the Audio signal of
pin1, 9 of IC601 normal
Yes Check RO LO lines.
NO
Check the voltage of
Q601 Base.
0V
NO
Check/Replace Q601, Are the Audio signal of
IC101, Q602, D601, pin4, 6 of IC601 normal?
D602, R612, R614
Check the voltage of pin7
Yes of IC601
Check/Replace C614, C615, NO
D603, D604, Speaker
Yes
Check/Replace IC601
Check/Replace F802,
D814, L801
NO PICTURE/NO SOUND
(RASTER OK)
Does the Auto programs
operation?
Yes NO
NO NG
Is the CVBS signal of Check the voltage 5V,
pin13 of IC501 normal? 33V of TU101
Yes OK Check/Replace ZD102,
Check/Replace IC501
5V, 33V power lines
Go to NO PICTURE Check I2C BUS lines
Block. (SDA, SCL)
NO SOUND Blcok.
OK
Check/Replace TU101
NO RASTER
(SOUND OK)
Check the voltage of HT
of CPT Board
Normal Abnormal
Abnormal Abnormal
Check the voltage of HV, Check the Heater pulse of
G2 of CPT HT of T406
Normal Normal
Check/Replace T406 Check/Replace T406
Check/Replace P901A, Check/Replace
P901B, ZD904, IC901, Connector, FR915
D902~904, P901
NO COLOR
(Autoprograming, Picture OK)
Are the R-Y, B-Y signal of pin29, 30
of IC501 normal? NO
Check/Replace IC501,
Yes
X501, X502
Are the R-Y, B-Y signal of pin31, 32
of IC501 normal? NO
Check/Replace IC502.
Yes Check 12V line, R-Y, B-Y
line
Are R, G, B signal of pin19, 20, 21
of IC501 normal? NO
Yes Check/Replace IC501
Check/Replace P901A, P901B,
IC901
NO TELETEXT
Check the voltage 5V of
pin1 of IC805
Abnormal 48.~5.2V
Check the 5V line to be NO Check video signal pin9
correct. of IC701
NO
Check video signal at the Yes
pin38 of IC501
Check I2C BUS lines
Yes (SDA, SCL)
Check/Replace IC501
Check/Replace Q506,
OK
Q1101, C709
Check pin16, 17, 18, 20
of IC701
Abnormal
Check/Replace IC701,
X701, L701, R702, C713
Check/Replace
D505~508, C516~518