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TROUBLESHOOTING GUIDE
1. NO POWER
NO POWER (POWER INDICATOR OFF)
CHECK FUSE OK?
NO
TROUBLE IN FUSE (F901)
YES
CHECK C912 (+) VOLTAGE? (250VDC)
NO
TROUBLE IN D901
YES
CHECK Q902 DRAIN WAVEFORM (SQUARE WAVE COMES OUT?)
NO
TROUBLE IN IC901 or Q902
YES
CHECK D921, D922, D931, D924, D925, D926 VOLTAGE?
NO
TROUBLE IN D921, D922, D931, D924, D925, D926
YES
TROUBLE IN IC903
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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 VIDEO CARD, SIGNAL CABLE
YES
CHECK IC302 PIN 29, 32, 35 ?
NO
TROUBLE IN IC302
YES
CHECK IC303 PIN 2, 8, 12 ?
NO
TROUBLE IN Q330, Q331, Q332
YES
CHECK R, G, B CATHODE VOLTAGE?
NO
TROUBLE IN IC303
YES TROUBLE IN CRT 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 VOLUME OF FBT
MIN. (Counter-clockwise)
ROTATE SCREEN CONTROL VOLUME TO CLOCKWISE
OK
CHECK VOLTAGE AT D926 CATHODE (198V) D924 CATHODE (78V) IC911 OUT (12V) D932 CATHODE (7.5V)?
NO
TROUBLE IN PRIMARY CIRCUIT OF T901, T902
YES
CHECK IC202 (MICOM) PIN 5 (5V, HIGH), IC701 PIN 16 12V (HIGH)?
NO
TROUBLE IN SECONDARY CIRCUIT OF T901, T902
YES
TROUBLE IN IC202 (MICOM), IC701 (T/BASE), UPC1884ACT
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4. NO VERTICAL DEFLECTION
NO V-DEFLECTION (ONE HORIZONTAL LINE)
CHECK IC601 PIN 2 (15V)?
NO
TROUBLE IN T901 PIN 18
YES
CHECK IC601 PIN 4 (-12V)?
NO
TROUBLE IN T901 PIN 15
YES
CHECK IC701 PIN 8 (SAWTOOTH WAVE)?
NO
TROUBLE IN IC701
YES
TROUBLE IN IC601, VERTICAL OUTPUT CIRCUIT
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5. TROUBLE IN DPM
STAND-BY/SUSPEND/ OFF MODE FAILURE
CHECK IC202 (MICOM) PIN 42, 1 (H/V INPUT) SIGNAL? INPUT H/V SYNC
NO H / V SYNC SIGNAL
CHECK PC, (PC IS NOT GOING INTO DPM MODE)
CHECK IC202 PIN 6, 7 WAVEFORM? YES
NO
TROUBLE IN X201, IC202
CHECK IC202 PIN 17 (5V, HIGH)?
NO
TROUBLE IN IC202
YES
CHECK IC902 PIN 7 (15V)?
NO
TROUBLE IN Q903, IC916, D914
YES CHECK B+ LINE (12V, 15V, 78V, 5V) ?
NO
TROUBLE IN R938
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 IC202 PIN 22 (5V)?
NO
TROUBLE IN IC202 (MICOM)
YES
CHECK Q915 COLLECTOR VOLTAGE (0.5V)? YES
NO
TROUBLE IN D932, IC960
CHECK P903?
NO
TROUBLE IN P903
YES
CHECK RL902?
NO
TROUBLE IN RL902
YES
TROUBLE IN TH901, DEGAUSSING COIL
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7. NO TILT (ROTATION )
NO TILT (ROTATION)
CHECK IC603 PIN 8 VOLTAGE (15V) ?
NO
TROUBLE IN D922
YES
CHECK IC603 PIN 4 (-12V)?
NO
TROUBLE IN D931
YES
CHECK IC603 PIN 5?
NO
TROUBLE IN IC202 (MICOM)
YES
TROUBLE IN P609, TILT COIL CONNECTOR, TILT COIL
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8. TROUBLE IN OSD
NO OSD
CHECK IC301 PIN 4, 9 (5V) ?
NO
TROUBLE IN P302, D927
YES
CHECK IC301 PIN 5 (NEGATIVE H-PULSE COMES IN ?)
NO
TROUBLE IN Q301, P302
YES
CHECK IC301 PIN 10 (NEGATIVE V-PULSE COMES IN?)
NO
TROUBLE IN Q302, P302
YES
CHECK IC301 PIN 13, 14, 15 (IS THERE ANY SIGNAL WHEN OPERATING OSD CONTROL ?) YES TROUBLE IN IC302
NO
TROUBLE IN IC301, IC202
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