Samsung 400UX-2 Service Manual

Also see for SyncMaster 400UX-2: User manual Quick start guide Specifications Quick start guide Quick start guide

4-84. Troubleshooting4-5. No BNC VideoSymptom The LED power turns on but the screen is blank when the BNC cable is connected.-MajorcheckpointsCheck the BNC cable connections.Check whether the LVDS cable is connected correctly to the panel.Check whether the lamp connector of the panel is connected correctly to the SMPS board.---DiagnosticsIC304FT604 FT609CN302YesCheck the circuits surroundingCN801.NoDoes 5V appear at Pin 1 of CN302?Is the cable connection correct?Check the cable connectingthe BNC Sub board and theMain board.aNoYesDoes the waveform as shown in theimage appear at Pin 6 (H-sync) 8 andPin 8 (V-sync) 9 of C304?Check the IC304.NoYesDoes the TX** signal appear atPins 3 and 4 of FT604 and FT609respectively?The Scaler (IC303) isabnormal. Replace the mainboard.NoYesCheck the cable between the mainboard and paneland replace the LCD panel.Caution Make sure to disconnect the power before working on the SMPS board.