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TROUBLESHOOTING GUIDE
1. NO POWER
NO POWER (POWER INDICATOR OFF)

CHECK FUSE OK?

NO

TROUBLE IN FUSE (F901)

YES

CHECK C907 (+) VOLTAGE? (390VDC)

NO

TROUBLE IN D901

YES

CHECK IC903 PIN 3 WAVEFORM COME OUT?

NO

TROUBLE IN IC903

YES CHECK IC901 PIN 3 WAVEFORM COME OUT? YES

NO

TROUBLE IN IC901

CHECK D921, D922, D931, D924, D925, D926 VOLTAGE?

NO

TROUBLE IN D921, D922, D931, D924, D925, D926

YES TROUBLE IN IC911

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2. NO CHARACTER

NO CHARACTER

CHECK IC302 PIN 3, 8, 12 (12V), PIN 17 (5V)?

NO

TROUBLE IN P302, 5V, 12V LINE

YES

CHECK IC302 PIN 2, 6, 11 ?

NO

TROUBLE IN PC SIGNAL, SIGNAL CABLE

YES

CHECK IC302 PIN 29, 32, 35 ?

NO

TROUBLE IN IC302

YES

CHECK R, G, B CATHODE VOLTAGE?

NO

TROUBLE IN IC303

YES TROUBLE IN CDT SOCKET

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3. NO RASTER

NO VIDEO (POWER INDICATOR GREEN or ORANGE)

CHECK POWER INDICATOR GREEN or ORANGE ?

ORANGE

TROUBLE IN P302 SIGNAL CABLE

GREEN

CHECK SCREEN CONTROL KNOB OF FBT

MIN. (Counter-clockwise)

ROTATE SCREEN CONTROL KNOB TO CLOCKWISE

OK

CHECK VOLTAGE AT D912 CATHODE (190V) D909 CATHODE (85V) IC911 OUT (12V) D906 CATHODE (6.3V)?

NO

TROUBLE IN PRIMARY CIRCUIT OF T901

YES

CHECK IC401 (MICOM) PIN 11 5V (HIGH), IC701 PIN 10 12V (HIGH)?

NO

TROUBLE IN CDT SOCKET, BOARD

YES TROUBLE IN IC401 (MICOM), IC701

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4. NO VERTICAL DEFLECTION

NO V-DEFLECTION (ONE HORIZONTAL LINE)

CHECK IC601 PIN 2 (15V) ?

NO

TROUBLE IN T901 PIN 15

YES

CHECK IC601 PIN 4 (-12V)?

NO

TROUBLE IN T901 PIN 16

YES

CHECK IC701 PIN 12, 13 (SAWTOOTH WAVE)?

NO

TROUBLE IN IC701

YES

TROUBLE IN IC601, V-CIRCUIT

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5. TROUBLE IN DPM
STAND-BY/SUSPEND/ OFF MODE FAILURE

CHECK IC401 (MICOM) PIN 8, 9 (H/V INPUT) SIGNAL? INPUT H/V SYNC

NO H / V SYNC SIGNAL

CHECK PC, (PC IS NOT GOING INTO DPM MODE)

CHECK IC401 PIN 13, 14 WAVEFORM? YES

NO

TROUBLE IN X401, IC401

CHECK IC401 PIN 11 (5V, HIGH)?

NO

TROUBLE IN IC401

YES

CHECK IC401 PIN 19, 21 ?

NO

TROUBLE IN IC401

YES CHECK B+ LINE (12V, 15V, 80V, 5V) ?

NO

TROUBLE IN IC911
DPMS TABLE

Mode TROUBLE IN T901 or PC

Item

H / V SYNC ON / ON OFF / ON ON / OFF OFF / OFF

VIDEO NORMAL OFF(0V) OFF(0V) OFF(0V)

LED GREEN ORANGE ORANGE ORANGE

NORMAL STAND-BY SUSPEND OFF

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6. NO DEGAUSSING

NO DEGAUSSING

(

BUTTON MUST BE PRESSED.)

CHECK IC401 PIN 20 (5V)?

NO

TROUBLE IN IC401 (MICOM)

YES

CHECK Q908 COLLECTOR VOLTAGE (0.5V)? YES

NO

TROUBLE IN D914

CHECK P903?

NO

TROUBLE IN P901

YES

CHECK RL901?

NO

TROUBLE IN RL901

YES

TROUBLE IN TH901, DEGAUSSING COIL

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7. NO TILT (ROTATION )

NO TILT (ROTATION)

CHECK R213 VOLTAGE (12V) ?

NO

TROUBLE IN D913

YES

CHECK Q202 ?

NO

TROUBLE IN Q315

YES

CHECK IC401 ?

NO

TROUBLE IN IC401

YES

TROUBLE IN P202, TILT COIL CONNECTOR, TILT COIL

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8. TROUBLE IN OSD
NO OSD

CHECK IC301 PIN 4, 17 (5V) ?

NO

TROUBLE IN P302

YES

CHECK IC301 PIN 5 (NEGATIVE H-PULSE COMES IN ?)

NO

TROUBLE IN P302

YES

CHECK IC301 PIN 18 (NEGATIVE V-PULSE COMES IN?)

NO

TROUBLE IN P302

YES

CHECK IC301 PIN 8, 7 (IS THERE ANY SIGNAL WHEN OPERATING FRONT CONTROL ?) YES TROUBLE IN IC302

NO

TROUBLE IN IC301, IC401

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