Garmin Personal Navigator GPS 100AVD Owner's Manual page 20

Certain messages will remain on the Message Page after being viewed. If
this occurs, the Message Annunciator will be in view but will not flash.
If no messages exist on the Message Page, the Message Annunciator will
not be visible and the message page will appear as illustrated below.
Refer to Chapter 13 for a complete list of GPS 100 messages.
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