Tdog1

Within the navigation unit of my 2012 GL550, under "position", there is a compass, lat/longs, and what appears to be an inclinometer which I am supposing shows the relative angle of the vehicle to the earth. However, it never moves off of zero. I haven't climbed any really steep grades in it but I have gone up and down hills of at least 10-20% grade, but it still stays at zero. Does anyone have any info or experience with this?

Also, the compass only indicates a change in direction, in what looks like 20 or 30 degree increments, which isn't all that usefull for off-road use. Thoughts?