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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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