I thought back light was broken. But I think it just switched to black background. Took me a while to figure out that there is a setting to auto go to black background based on time of day. Does anyone know what time of day it does this? The time is not in the manual or the FAQ.
I have a Garmin 496 (Aviation) and the display changes based on the theoretical sunrise/sunset. I would assume it would be the same on the 705.
It may do it according to avaliable light like a navigation system in a car
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