The crop region and view range must intersect for a section tag to be visible.
The section tag is visible in plan, elevation, and other section views, provided its crop region intersects the view range. For example, if you resize the crop region of the section view, so that it no longer intersects the plan view’s view range, the section symbol does not appear in the plan view.
Section symbols can display in elevation views even if their crop boundary is turned off. The section displays in elevation if the section line intersects the elevation clip plane. To view and modify the position of the elevation clip plane, select the arrowhead of an elevation symbol in a plan view, and the clip plane appears with drag controls on it. If you resize the clip plane such that it no longer intersects the section line, the section is not visible in the elevation view.