Why is the contrast poor on the LCD panel?
If you observe poor contrast on the LCD panel, P/N AND94GST, shipped with your ML410 and you have a RoHS version of the LCD panel (identified by RoHS notation on the part number sticker located on the back of the LCD unit), make the following adjustments. Otherwise, no action is required
NOTE: The contrast voltage setting of the RoHS version of the LCD panel differs from the non-RoHS version even though the manufacturer maintains a single part number for both versions.
Adjust the LCD contrast voltage by changing resistor R409 as follows:
100 ohms, 0603 package, 1% tolerance, 1/16W
249 ohms, 0603 package, 1% tolerance, 1/16W
NOTE: R409 is located on the back side of the ML410 board near the LCD panel J13 header connection.