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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 - 19 - 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 - 20 - 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 - 21 - 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 - 22 - 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 - 23 - 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 - 24 - 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 - 25 - 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 IC3