When I got to the menue under "navigation" I can see the de-clutter waypoints tab with an arrow to the bottom right. When I hit the right curser arrow, nothing happens- no additional menu to select from- but I can see the contour lines on the chart disappear for maybe 10 seconds- then they re- appear. Is the menu supposed to be giving me the option to de=clutter - yes or no= or is that the way it is supposed to work?