Findout more info about GARMIN Forerunner 55: If you want to know how to adjust backlight
Toadjust the brightness of the backlight, it might be necessary to press fn at the same time as the backlight key to dim or brighten the backlight. You can also press the key with the backlight icon two or three times in a row. The keyboard dims and brightens.ExpertPicture Settings, or EPS, is a feature included with the Roku® mobile app that enables you to fine-tune key picture quality settings that are not 1 restart computer. 2. when the dell logo appears press either f12 or the delete key, might depend on your model. this is to open the boot menu. 3. select BIOS setup. 4. go to the system configuration tab, inside here should be the backlight settings for AC and battery. you can pick the settings you want!!