Trouble with GPS approach

Question

when I set up a GPS Approach Xp 11 follows the flight plan but the vertical approach does not kick in

I end up either too low or fly right over the airport I am trying to land at

I'm flying the Cessna 172

Am I activating the approach to soon or too late?

I have the AP on.  The Nav on and the Appr on

The GPS follows the horizontal flight plan but not vertically

Driving me nuts.  HELP please

Answer 1

I'm not incredibly familiar with the GPS and using it to fly with the autopilot, but I understand the X-Plane G430 and G530 units have a passive VNAV capability only, and thus the pilot must (manually) manage the climbs and descents associated with the flight plan.

Answer 2

1. Use G-1000 and autopilot in Cessna 172

2.Select VOR  as waypoint  on or near destination airport

3. Use NAV-1 to enter localizer frequency of desired runway at airport

4. Ten miles before reaching VOR waypoint select CDI / LOC from G-1000 and select approach on autopilot - then wait and watch the magic.