Hello,
neither do I recall seeing a NAV WPT below 400
On the Jeppesen manual "INTRODUCTION" there is a section called:
"Aeronautical information Navdata database and Charts"
Here is a copy and paste
Virtually all departures in the database include a climb to 400 ft above the airport prior to turning because of requirments in state regulations and recomendations. The "400-Foot Climb" is not depicted on most charts and is not part of the official procedure.
A bit later, in the same section: "FINAL COCKPIT AUTHORITY, CHARTS OR DATABASE?"
There are differences between information displayed on your airborne avionic navigation system and the information shown on Jepp Charts.
THE CHARTS, supplemented by notams, ARE THE FINAL AUTHORITY