Thanks. Planned obsolescence I guess. The manual doesn't even mention a backlight or any display lighting at all. The only mention of the word 'light' or 'lit' is in connection with indicator or warning LEDs.
Set Screen Contrast
The default setting for the LCD screen is 3. Screen
contrast levels can be adjusted from 1 to 5 units for low
or high lighting conditions.
1. Check that the green power LED is on.
2. Press Menu.
3. Press Select to select “Settings”.
4. Use the Up or Down arrow to scroll to “Contrast
5. Press Select. Screen will show current contrast
6. Press Select to change the setting and use Up or
Down to change number.
7. Press Enter to save. To cancel any changes, press
Escape to exit without saving.
8. Press the Escape button to exit.
Oh sorry, I thought you meant about the light. The contrast doesn't seem to affect the light. It's like a little night light for my pad I guess. I only noticed it tonight when I could see it from across the yard glowing under the display cover.