You can set the timer to start at night and end in the morning so that the device can automatically dim itself at night and light up in the morning: 1. Press CLOCK 2. Press SELECT 3. Press DOWN repeatedly to highlight Auto Brightness 4. Press SELECT two times 5. Press UP/ DOWN repeatedly to switch Auto Brightness function on or off 6. Press BACK to return 7. Press DOWN repeatedly to highlight Timer Settings, and then press SELECT 8. Press or hold HOUR+ below the second display or DOWN to select the desired start time 9. Press or hold HOUR+ below the second display or DOWN to select the desired end time 10. Press BACK to exit setting Important: Make sure you have set the clock time before you activate auto brightness function.