Introduction

This manual includes information for the following products:

GPSMAP® 421/421s

GPSMAP 451/451s

GPSMAP 521/521s

GPSMAP 526/526s

GPSMAP 551/551s

GPSMAP 556/556s

Tips and Shortcuts

Press HOME from any screen to return to the Home screen.

Press MENU from any of the main screens to access advanced settings.

Press and release thePower key to adjust the display settings.

Manual Conventions

In this manual, when you are instructed to select an item, small arrows (>) appear in the text. They indicate that you should highlight a series of items on the screen using the Rocker, and press the SELECT key after each item. For example, if you see “select Charts > Navigation Chart,” you should highlight Charts, and press SELECT. Then highlight Navigation Chart, and press SELECT again.

Introduction

Quick Links

Turning the Unit On or Off: page 2.

Acquiring GPS Satellite Signals: page 5.

Inserting and Removing SD Cards: page 6.

Restoring the Original Factory Settings: page 5.

Using the Navigation Chart: page 7.

Changing the Navigation Chart Settings: page 11.

Navigating to a Destination: page 23.

Creating and Using Waypoints: page 25.

Configuring System Settings: page 47.

Using Sonar: page 56.

Alarms and Messages: page 68.

GPSMAP 400/500 Series Owner’s Manual

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