Garmin GHC 20 User Manual

GHC™ 20

Owner’s Manual

April 2013 190-01610-00_0A Printed in Taiwan

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right to change or improve its products and to make changes in the content of this manual without obligation to notify any person or organization of such
changes or improvements. Go to www.garmin.com for current updates and supplemental information concerning the use of this product.

Garmin® and the Garmin logo are trademarks of Garmin Ltd. or its subsidiaries, registered in the USA and other countries. GHC™ and Shadow Drive™ are
trademarks of Garmin Ltd. or its subsidiaries. These trademarks may not be used without the express permission of Garmin.

NMEA®, NMEA 2000®, and the NMEA 2000® logo are registered trademarks of the National Marine Electronics Association.

Introduction

WARNING

See the Important Safety and Product Information guide in the
product box for product warnings and other important
information.

You are responsible for the safe and prudent operation of your
vessel. The autopilot is a tool that will enhance your capability to
operate your boat. It does not relieve you from the responsibility
of safely operating your boat. Avoid navigational hazards and
never leave the helm unattended.

Always be prepared to promptly regain manual control of your
boat.

Learn to operate the autopilot on calm and hazard-free open
water.

Use caution when operating the autopilot near hazards in the
water, such as docks, pilings, and other boats.

The autopilot system continuously adjusts the steering of your
boat to maintain a constant heading. In addition to the basic
heading-hold functionality, the system allows manual steering
and several modes of automatic-steering functions and
patterns.

You can operate the autopilot system using the helm control
device. Using the helm control, you engage and steer, set up,
and customize the autopilot system.

For information about installing, see the installation instructions
for each device.

Device Overview

Autopilot status/autopilot status indicator.

À

"Standby" appears in yellow, and the autopilot status indicator
appears in yellow when the device is in standby mode.

"Heading Hold" appears in green, and the autopilot status indicator
appears in green when the device is in heading hold.

Heading trend indicator.

Á

Actual heading (in standby mode)

Â

Intended heading (with the autopilot is engaged)

Rudder position indicator (This functionality is available only when

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a rudder sensor is connected.)

Standby Mode

CAUTION

The autopilot does not steer the boat in standby mode. You are
responsible for controlling the helm, when in standby mode.

In standby mode, you can engage the autopilot and adjust
settings.

"Standby" appears in yellow and the yellow LED indicator
appears in the upper-right corner of the screen when the device
is in standby mode.

Select to place the autopilot in standby mode and return to the

À

heading screen.

Select to open a menu or perform the function listed above the key.

Á

Select to open the display settings menu.

Â

Press twice to adjust the backlight.
Hold to turn off the device.

Heading Screen

The heading screen displays the status of the autopilot.

Powerboat Autopilot Operation

Heading Hold

You can engage the autopilot heading hold function to maintain
your current heading without steering the helm.

Engaging the Autopilot

When you engage the autopilot, the autopilot takes control of
the helm and steers the boat to maintain your heading.

From the heading screen, select Engage.
"Heading Hold" appears in green at the top of the heading

screen, and a green icon appears in the upper-right corner of
the screen when the device is in heading hold. Your intended
heading shows in the center of the heading screen.

Heading Adjustment

When the autopilot is engaged, you can adjust the heading
using the keys on the helm control or using the helm if your
autopilot is equipped with Shadow Drive™ technology.

Enabling Shadow Drive

NOTE: The Shadow Drive feature is for use only on power

planing hull or power displacement hull boats.

Select Menu > Setup > User Autopilot Setup > Shadow
Drive.

Adjusting Shadow Drive Sensitivity

Select Menu > Setup > User Autopilot Setup > Shadow
Drive Sensitivity.

Adjusting the Heading with the Helm

NOTE: You must enable the Shadow Drive feature before you

can adjust the heading using the helm (page 1).

Introduction 1