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Trouble Shooting
1. NO PICTURE ( SOUND OK )
CVBS Signal ?
Check MAIN1 Q026(E) Waveform. (2Vpp)
YES NO
NO
Check around
Waveform of AV Board Q200(E) ? Check Tuner(TU101)VIDEO output
IC200
YES
NO
Waveform of AV Board IC202 #11 ? Check around IC201, 202
YES
NO
Waveform of MAIN1 IC501 #63 ? Check AV Board VQ202(E)
YES
NO
Check around IC501 #37, #38, #39
Waveform of MAIN1 P503 #5, #7, #9 ?
Output circuit.
YES
Waveform of CPT Board NO Check around CPT Board
IC901R/G/B #3 ? Q901R/G/B
YES
NO
Waveform of CPT Socket Cathode
Check around IC901R,G,B
(RK/GK/BK) ?
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2. NO SOUND (PICTURE OK)
< RF >
Waveform of AV Board IC7 01 Waveform of
NO NO Check
#47,48,50,51,53,54,56,57 Check JA202 Jack MAIN1 Q022(E)
at each Mode ? ( SIF ) ? TU101
YES YES
Waveform of Check
YES NO
AV Board IC701 around
#67 ? Q706
Waveform of AV Board NO
IC701 #27,#28,#25 ? Check around IC701
YES
Waveform of MAIN1 NO Check around AV Board
IC601 #7,#11 IC602 #7 ? Q703,704,705
YES
Waveform of MAIN1 NO Check around
IC601 #2,#4 IC602 #4 ? IC601,602
YES
Check AV Board JA501,
Main1 P602 Connector
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3. NO PIP
Waveform of AV Board Waveform of MAIN1 Waveform of PIP
IC200 #27,29,31 ? Q027(E) ? Board IC1201 #28 ?
NO
Check JA202
YES YES
NO
Waveform of AV Board Check AV Board
IC200 #13 ? IC200, Q201
Check
YES NO ScartJack
JA204
YES
NO
Waveform of PIP Board Check PIP Board
IC1201 #26 ? Q1206
YES
Waveform of PIP Board NO
IC1201 #15~#18 ? Check around IC1201
(R,G,B, FB)
YES
Waveform of MAIN1 NO
Check PIP Board
IC501 #45~#48 ?
Q1203,1204,1205
( R,G,B FB )
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4. NO Teletext(Picture OK)
Waveform of MAIN1
IC501 #59 ?
YES
NO Check PIP Board
Waveform of IC001 #12 ?
IC1205 #2, #4
YES
Check OPTION1 TEXT Code
(SVC MODE)
5. NO OSD (ON SCREEN DISPLAY)
Waveform of MAIN1 IC001#19,#20 ? Horizontal, Vertical Fly Back Input
NO
YES
Check DEF. Board.
Check MAIN1 Q010,Q009,Q002
NO
Waveform of MAIN1 IC001 #38,39,40,41 ? Check input power of IC001
(R,G,B,FB)
YES
NO
Waveform of MAIN1 IC501 #41,42,43,44 ?
(R,G,B,FB) Check around Q014, Q015, Q016, Q017
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6. NO POWER ON
6.1 MICOM PART CHECK
Check input voltage of NO
Check SMPS Board
IC001#9,11,13,30,37,42,44
YES
Check IC001 #34,35 NO
Replace X001
(OSC)
YEs
NO
Check IC001 #3, 4 (SCL,SDA) Replace Q003, Q004
YES
LOW
Check IC001 #46 (ABN) CheckAbnormnal Circuit
HIGH
Check IC001 #24 ( IR ), NO
Check P004AP connector
#47~52 (Key In)
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7. NO VFD OPERATION
Check AV Board IC750 #5 NO
Sound signal. Check IC701sound output
YES
NO
Check IC750 #3 output Check around IC750
YES
NO
Check IC001 #18, 21, 22 Check Q008, 007
YES
NO
Check IC001 #23, 25, 27 Check Q011, Q012
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8.NO RASTER
Check +B voltage
at Pin1 of P805A.
Normal 0V
Is the voltage at Open
Check F801.
Pin 15,17 of IC501 3.3V? No
Check/Replace
Check 5V, 9V, F801, D802,
Yes OK
12V lines IC801,IC802.
Does the square
Check the voltage 0V
waveform from pin50
No of IC501 appear? of C812(+).
Yes
Check/Replace Check I2C Check/Replace
IC501 Yes D802.
Bus lines
(SDA, SCL)
Is the waveform at Check the voltage Lower than 6V
No collector of Q402 normal? at pin 4 of IC801.
Check/Replace Check/Replace
Q402, T401. Yes D805,Q801,
6~ 8V ZD801.
Is the waveform of collector
No of Q403 normal?
Check/Replace IC887, IC871.
Check the secondary voltage
Check/Replace
Yes are shorted
Q403.
Check/Replace
T401.
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9.INCORRECT CONVERGENCE
Does the static convergence
correct?
Incorrect Dynamic Incorrect Static
Check the input voltage at Readjust static convergence
P201. by remote controller
Normal Abnormal Not controlled Controlled
Check pulse pin 125 Check voltage on the Are there pulse signal
O.K
of IC2051 (4MHz) SMPS PCB at pin 121 of IC2051
Y Abnormal Abnormal Normal
Check/Replace Check VBLK,HBLK at pin Are there VBLK, HBLK pulse Check/Repla
IC2051 2,4 of P404. at pin 3,4 of P404. ce Q2201
Y No Abnormal Normal
Check/Replace Check Check VBLK, HBLK
Check/Replace
IC2002 HBLK,VBLK on signal on the
IC2051
the DEF PCB DEF PCB
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