Troubleshooting - ViewSonic VA902B - 19" LCD Monitor Service Manual

6. TROUBLE SHOOTING
1. Common Acknowledge
If you change the interface board, be sure that the U105, U106 and U103 these three components also changed to the new I/F
board because there was program inside. If not, please re-write EDID or upload firmware into MCU via VGA Cable.
If you adjust clock and phase, please do it at the condition of Windows shut down pattern.
If you confirm the R.G.B. color is normal or not, please do it under 16-grey scalar pattern.
This LCM is analog interface. So if the entire screen is an abnormal color that means the problem happen in the analog circuit
part, if only some scale appears abnormal color that stand the problem happen in the digital circuit part.
If you check the H/V position, please use the crosshatch pattern.
This LCM support more than 30 timing modes, if the input timing mode is out of specification, the picture may appears
abnormally.
If brightness uneven, repairs Inverter circuit or change a new panel.
If you find the vertical line or horizontal line lost on the screen, please change panel.
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VA902/b