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TROUBLE SHOOTING GUIDE
1. NO POWER
NO POWER
CHECK C910 NO TROUBLE IN
DC VOLTAGE? F901, R901, AND R910,
D901 OPEN/SHORT
DC=MORE THAN 150V
YES
TROUBLE IN
CHECK CHECK
NO NO IC901, IC902, IC952,
T901 IC901
Q901, R917, R920,
PIN 3? PIN 6 ?
20V
AND R921
YES
YES TROUBLE IN
Q901, R917, R920,
AND R921
NO OUTPUT
CHECK VOLTAGE CHECK
SMPS 2nd NO TROUBLE IN Q501,
Q501, 2nd DC
DC VOLTAGE ? VOLTAGE LINE ? 2nd DC VOLTAGE LINE
6.3V/ 12V/ 12.5V
14V/ 72V
YES
CHECK
NO TROUBLE IN
IC952 PIN 7
IC952
VOLTAGE (5V)?
YES
TROUBLE IN
OTHER PRIMARY CIRCUIT
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2. NO CHARACTER
NO CHARACTER
CHECK NO TROUBLE IN
IC201 PIN 17 (8V)? Q203, D211,
12V LINE
YES
CHECK TROUBLE IN
NO
IC201 PIN 2, 4, 6 ? PC SIGNAL,
C201, C202, C203
YES
CHECK NO TROUBLE IN
IC201 PIN 15, 19, 22 ? IC201
1.2v
YES
CHECK TROUBLE IN
NO
IC301 PIN 3, 4, 10 ? IC301
YES
CHECK TROUBLE IN
NO
R, G, B CATHODE Q301, D301, D302
VOLTAGE?
NORMAL=75~110V
YES
TROUBLE IN
CRT SOCKET
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3. NO RASTER
NO RASTER (LED COLOR IS GREEN)
CHECK
NO TROUBLE IN
DPM2 OUTPUT, CRT HEATER
VOLTAGE? (6.2 0.3V) 6.3V LINE, Q951, Q952,
MICOM PIN 6 (HIGH)
YES
CHECK
IC701 PIN 7 NO TROUBLE IN
WAVEFORM ? IC701, IC701 B+
4V
YES
CHECK TROUBLE IN
FBT PIN 2 NO
B+(50V) LINE OPEN,
B+ VOLTAGE ? Q501, R506, R507,
IC701 PIN 6, R730
DC 135~140V 0.8V
( )
YES
CHECK TROUBLE IN
IC701 PIN 16 NO
H-OUT CIRCUIT,
WAVEFORM? Q702, Q703, IC701 PIN 1
5V
( )
YES
CHECK TROUBLE IN
NO
CRT G1 Q803, Q804 (OPEN)
VOLTAGE? G1= LESS THAN -120V Q801 (BASE: HIGH)
(LOW AT NORMAL)
DC: -20~-40V
YES
TROUBLE IN
BRIGHT CIRCUIT
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4. TROUBLE IN H-SIZE, S-PCC, TRAPEZOID
NO ADJUSTED H-SIZE
CHECK NO TROUBLE IN
IC701, PIN 32
IC701
(5V)?
YES
NO TROUBLE IN
CHECK
IC701 PIN 11? IC701
YES
CHECK VOLTAGE OF
C807 (H-SIZE) DC 0.2~4V? NO TROUBLE IN
C406 (TRAP.) DC 0~5V? IC401 (MICOM)
C407 (S-PCC) DC 0~5V?
YES
TROUBLE IN
CHECK NO
IC801, Q817
IC801 PIN 1
YES
CHECK NO TROUBLE IN
Q816 COLLECTOR? Q816, Q807, Q808, D704
YES
TROUBLE IN
L801, D704, Q703
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5. TROUBLE IN H-LINEARITY
UNBALANCED OF H-LIN.
CHECK NO TROUBLE IN
IC401 PIN 7, 8, 9? IC401 (MICOM)
YES
CHECK NO TROUBLE IN
Q809, Q810, Q811, Q812, Q809~Q814
Q813, Q814? D804, D805, D806
YES
CHECK NO TROUBLE IN
IC803 PIN 3? DC-DC CONVERTER
1.7V
1.4V
YES
31K 60K
CHECK TROUBLE IN
NO
Q815 EMITTER IC803, Q815, R846
VOLTAGE?
YES
TROUBLE IN Cs SIGNAL TABLE
L802, D807 HORIZONTAL Cs 0 Cs 1 Cs 2
FREQUENCY(fH)
30~33kHz L L L
33.1~43kHz L H L
43.1~52kHz H H L
52.1~60kHz H L H
60.1~67kHz H H H
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6. NO VERTICAL DEFLECTION
NO V-DEFLECTION
(ONE HORIZONTAL LINE)
TROUBLE IN
CHECK NO Q601, Q602
IC601 PIN 3 IC401 (MICON) PIN 5 (HIGH),
(14V)?
IC601
YES
CHECK NO TROUBLE IN
IC601 PIN 7
H-OUT CIRCUIT, D603
(38V)?
YES
CHECK NO TROUBLE IN
IC701 PIN 12, 13? IC701
3V
YES
TROUBLE IN
IC601, V-CIRCUIT
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7. NO CONTRAST
NO CONTRAST
TROUBLE IN
CHECK NO IC403, Q401
Q401 COLLECTOR?
ABL-OUT VOLTAGE
(11V AT BLACK PATTERN)
4v
YES
CHECK NO TROUBLE IN
ABL-OUT
Q706, Q705, Q704
VOLTAGE?
YES
CHECK NO TROUBLE IN
IC201 PIN 13? IC201
DC 0.8~3.5V
YES
TROUBLE IN
CONTRAST LINE
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8. TROUBLE IN OSD
NO OSD (MUST BE PRESSED SELECT BUTTONS)
CHECK NO TROUBLE IN
IC403 B+ ? 5V LINE
DC5V YES
CHECK
IC403 PIN 4, 5 NO TROUBLE IN
WAVEFORM? IC601 PIN 8,
FBT PIN 6
Pin 4
5V YES
Pin 5
CHECK
IC403 PIN 3 NO TROUBLE IN
WAVEFORM ? IC403, IC201
H+V
5V
YES
CHECK NO TROUBLE IN
IC403 PIN 19, 20, 21? IC403, IC201
H+V
5V
YES
TROUBLE IN
OSD PERIPHERAL
CIRCUIT
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9. TROUBLE IN DPM
OFF MODE FAILURE (NO OFF MODE)
CHECK
CHECK PC,
IC401 (MICOM) INPUT H / V SYNC SIGNAL
(PC IS NOT GOING INTO
PIN 35, 28 (H / V INPUT)
DPM OFF MODE)
SIGNAL?
NO H / V SYNC
CHECK
IC403 PIN 9 NO TROUBLE IN
WAVEFORM? X401, IC403
5V
YES
8MHz
CHECK
NO (DPM: 5V) TROUBLE IN
IC401 (MICOM)
IC401 (MICOM)
PIN 5, 6 ?
NORMAL: 5V
YES
DPM: 0.2V
CHECK
NO TROUBLE IN
B+ LINE (6.3V/ 12V/
14V/ 73V) ? B+ LINE
(AT DPM OFF MODE;
YES Q951, Q953, Q601: TURN OFF
IC952 PIN 6: 0V)
TROUBLE IN
PC
DPMS TABLE
Item H / V SYNC VIDEO LED
Mode
NORMAL ON / ON NORMAL GREEN
STAND-BY OFF / ON OFF(OV) GREEN/ORANGE
SUEPEND ON / OFF OFF(OV) BLINKING
OFF OFF / OFF OFF(OV) ORANGE
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10. NO DEGAUSSING
NO DEGAUSSING ( BUTTON MUST BE PRESSED)
CHECK NO TROUBLE IN
IC401 PIN 14 IC401 (MICOM)
(5V)?
YES
CHECK
NO TROUBLE IN
Q902 COLLECTOR
Q902, RL901
VOLTAGE?
DC 0.2V
YES
CHECK NO TROUBLE IN
P902? P902
YES
CHECK
NO TROUBLE IN
RL901?
RL901
YES
TROUBLE IN
TH901, DEGAUSSING
COIL
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