LG FLATRON L1550S-SN - No Raster (Mstar) Troubleshooting

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3. NO RASTER (OSD IS NOT DISPLAYED) – Mstar
NO RASTER
(OSD IS NOT DISPLAYED)
NO
NO
NO
TROUBLE IN CABLE
OR LCD MODULE
CHECK U801 (17", 19")
CHECK U803 (15")
1. CHECK PIN122, 123
SOLDERING CONDITION
2. CHECK X501
3. TROUBLE IN U201
CHECK CONNECTION
LINE FROM D-SUB TO
U501
YES
YES
YES
U201
PIN 18, 90
3.3V?
U201
PIN96, 97
OSCILLATE AS
12MHZ?
U501
PIN43 IS 48KHz H-SYNC?
PIN44 IS 60Hz V-SYNC?
IS PULSE APPEARED
AT SIGNAL PINS?
AT MODE 12?
1
2
1 2
Waveforms
U201-#96, 97
U501-#43 H-SYNC
2
U501-#44 V-SYNC