Garmin GNS 430W, GPS 400W, GNC 420W Quick Reference Guide, GI 275

400W Series

Quick
Reference

190-00356-01 Rev K

© 2006-2016 Garmin Ltd. or its subsidiaries

This manual reflects the operation of Main System Software version 2.00, 3.00, 4.00, 5.00, 5.10, 5.30, or later. Some differences in operation may be observed
when comparing the information in this manual to earlier or later software version.

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content without obligation to notify any person or organization of such changes or improvements. Visit the Garmin Web site (www.garmin.com or

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Garmin®, GPSMAP®, AutoLocate®, TracBack®, Apollo, SafeTaxi®, FliteChart®, and MapSource® are registered trademarks of Garmin Ltd. or its sub­sidiaries and may not be used without the express permission of Garmin. NavData® is a trademark of Jeppesen, Inc.; XM® is a registered trademark of XM
Satellite Radio, Inc.

January 2016 Part Number 190-00356-01 Rev K Printed in the USA

) for current updates and supplemental information concerning the use and operation of this and other Garmin products.

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Graphic Moving

Comm Freq

Flip/Flop

Power and Comm

Volume/Squelch

Photocell for

Auto-Dimming

Nav Freq

Window

Comm Freq

Window

Map Display and

Navigation Info

Range Keys

Direct-To Key

Menu Key

Terrain Database Card

Aviation Database Card

Nav Radio

Volume

Nav Radio Freq Flip/Flop

Large Knob

Comm/VLOC

Freq (MHz)

Small Knob

Comm/VLOC

Freq (kHz)

Terrain, Flight

Phase, and

GPS Integrity

Annunciator

Cam
Lock

Navigation

Source: GPS,

VLOC, or
GPS-PTK

CDI
Key

OBS
Key

Message

Key

Clear Key

Enter Key

Waypoint and

arrival alerts, turn

advisories, function,

and page number

Large Knob

Small Knob

(Cursor - Press to

activate)

Procedure Key

Flight Plan

Key

WARNINGS, CAUTIONS, and NOTES

WARNING: VNAV is to be used for advisory purposes only.
VNAV messages or vertical speed required should not be
used to maintain terrain or ATC clearances. Terrain and ATC
clearances are the sole responsibility of the pilot.

WARNING: The altitude calculated by the 400W-series
is geometric height above mean sea level and could vary
significantly from altitude displayed by pressure altimeters in
aircraft.

WARNING: The Jeppesen database incorporated in the
400W-series must be updated regularly in order to ensure
that its information is current. Updates are released every
28 days. A database information packet is included in your
400W-series package. Pilots using an out-of-date database
do so entirely at their own risk!

WARNING: Do not use data link weather information for
maneuvering in, near, or around areas of hazardous weather.
Information contained within data link weather products may
not accurately depict current weather conditions.

WARNING: Do not use the indicated data link weather
product age to determine the age of the weather information
shown by the data link weather product. Due to time delays
inherent in gathering and processing weather data for data
link transmission, the weather information shown by the
data link weather product may be significantly older than the
indicated weather product age.

CAUTION: GPS receivers operate by receiving and decod­ing very low power radio signals broadcast by satellites. It
is possible that in some situations other radio equipment
or electronic equipment used in close proximity to a GPS
receiver may create electromagnetic interference (EMI) which
may affect the ability of the GPS receiver to receive and
decode the satellite signals. In such event, the interference
may be reduced or eliminated by switching off the source of
interference or moving the GPS receiver away from it.

CAUTION: The Global Positioning System is operated by the
United States government, which is solely responsible for its
accuracy and maintenance. The system is subject to changes
which could affect the accuracy and performance of all GPS
equipment. Although the Garmin 400W-series are precision
electronic NAVigation AIDs (NAVAID), any NAVAID can be
misused or misinterpreted and therefore become unsafe.

CAUTION: Use the
risk of unsafe operation, carefully review and understand all
aspects of this Owner’s Manual and the Flight Manual Supple­ment, and thoroughly practice basic operation prior to actual

400W-series

at your own risk. To reduce the

use. When in actual use, carefully compare indications from the
400W-series
information from other NAVAIDS, visual sightings, charts, etc.
For safety, always resolve any discrepancies before continuing
navigation.

CAUTION: The electronic chart is an aid to navigation and
is designed to facilitate the use of authorized government
charts, not replace them. Land and water data is provided
only as a general reference to your surroundings. The posi­tional accuracy of the land and water data is not of a preci­sion suitable for use in navigation and it should not be used
for navigation. Only official government charts and notices
contain all information needed for safe navigation – and, as
always, the user is responsible for their prudent use.

CAUTION: The Terrain feature is for supplemental awareness
only. The pilot/crew is responsible for all terrain and obstacle
avoidance using information not provided by the 400W-series
Terrain feature.

CAUTION: The Garmin 400W-series does not contain any
user-serviceable parts. Repairs should only be made by an
authorized Garmin service center. Unauthorized repairs or
modifications could void your warranty and authority to
operate this device under FCC Part 15 regulations.

NOTE: The GNS 400W-series units use a different database
than in the legacy units. The databases are incompatible
between units. The GNS 400W-series units must use a WAAS
enabled database.

NOTE: This product, its packaging, and its components
contain chemicals known to the State of California to cause
cancer, birth defects, or reproductive harm. This notice is be­ing provided in accordance with California’s Proposition 65. If
you have any questions or would like additional information,
please refer to our website at www.garmin.com/prop65.

NOTE: It is the pilot’s responsibility for initial missed ap­proach guidance in accordance with published procedure. The
unit may not provide correct guidance until established on a
defined leg.

NOTE: GPS level of service annunciations (LPV, ENR, etc.)
are not applicable to the external CDI (or HSI) when VLOC is
active.

to all available navigation sources, including the

190-00356-01 Rev K

1

MODEL DESCRIPTIONS

Model Descriptions

This guide covers the operation of the GPS 400W, GNC

The GDL 69A can also allow you to subscribe to XM audio

services.
420W, GNC 420AW, GNS 430W, and GNS 430AW. In
general, all models will be referred to as the 400W-series,
except where there are physical or operational differences.
The 400W-series units are 6.25” wide and 2.66” high. The
display is a 240-by-128 pixel color LCD. The units include
two removable data cards: one with a Jeppesen database
(inserted in the left-most card slot) and the second is a Ter­rain database (inserted in the right-most card slot).

GPS 400W

The GPS 400W is a GPS-only unit with a WAAS GPS
engine and is TSO C146a certified for en route, terminal,
precision, and non-precision approaches. The GPS 400W
can simultaneously give aviators vital approach information
and weather and traffic data in relation to their position
on a color moving map display. Thanks to a high-contrast
color display, the information can be easily read from wide
viewing angles even in direct sunlight. Its color moving
map features a built-in database that shows cities, high­ways, railroads, rivers, lakes, coastlines, and a complete

GNC 420W and GNC 420AW

The GNC 420W and GNC 420AW include all of the
features of the GPS 400W, and also include an IFR certified
airborne VHF communications transceiver. This multipur­pose unit is available with either a 10-watt (GNS 420W)
or 16-watt (GNS 420AW) Com transmitter. Since the only
difference between these two units is the power of the
communications transmitter, references to the GNC 420W
will also include the GNC 420 AW.

Jeppesen aviation database. The Jeppesen aviation database
(can be updated with a front-loading data card) contains
all airports, VORs, NDBs, Intersections, FSS, Approach,
DPs/STARs, and SUA information. The obstacle and terrain
databases provide an aid to navigation to help you work
with approved navigation charts.

Pilots will enjoy the GPS 400W as a multi-function
display (MFD), especially when it is coupled with traf­fic, lightning detection, and weather interfaces like Ryan
TCAD, TIS from the Garmin GTX 3xx transponders, L3
SKYWATCH™, or STORMSCOPE® WX 500. With the
FDE prediction program included with the Trainer CD, the
GPS 400W may be used for oceanic or remote operations.
For the latest in graphical and textual weather information,
the GPS 400W can connect to XM Satellite Radio’s XM
WX Weather Service via the GDL 69/69A datalink receiver.

2

190-00356-01 Rev K

GNS 430W and GNS 430AW

The GNS 430W and GNS 430AW include all of the
features of the GPS 420W/420AW, and also include IFR
certified airborne VOR/Localizer and Glideslope receivers.
This multipurpose unit is available with either a 10-watt
(GNS 430W) or 16-watt (GNS 430AW) Com transmitter.
Since the only difference between these two units is the
power of the communications transmitter, references to the
GNS 430W will also include the GNS 430 AW.

Helicopter Installations

In Helicopter installations, the ownship icon is set to
a helicopter. When present, HTAWS will be used instead
of TAWS. See the Garmin Optional Displays Pilot’s Guide
Addendum P/N 190-00356-30 Rev G, or later, for HTAWS
information.

GPS 400W

GNC 420W

GNC 420AW

GNS 430W

GNS 430AW

KEYS AND KNOBS

Left-hand Keys and Knobs

In the GNC 420W and the GNS 430W, the

k

j

y

v

COM power/volume knob controls unit
power and communications radio volume.
Press the knob momentarily to enable/disable
automatic squelch control.

In the GNS 430W, the VLOC volume knob

controls audio volume for the selected VOR/
Localizer frequency. Press momentarily to
enable/disable the ident tone.

In the GNC 420W and GNS 430W, the large

left knob is used to tune the megahertz
(MHz) value of the standby frequency for
the COM transceiver or the VLOC receiver,
whichever is currently selected by the tuning
cursor.

In the GNC 420W and GNS 430W, the small

left knob is used to tune the kilohertz (kHz)
value of the standby frequency for the COM
transceiver or the VLOC receiver, whichever
is currently selected by the tuning cursor.
Press this knob momentarily to toggle the
tuning cursor between the COM and VLOC
windows.

COM power/

volume

VLOC volume

Small left knob

COM flip-flop

VLOC flip-flop

Large left knob

In the GNC 420W and GNS 430W, the COM

W

V

flip-flop key is used to swap the active and
standby COM frequencies. Press and hold to
select emergency channel (121.500 MHz).

In the GNS 430W, the VLOC flip-flop key

is used to swap the active and standby VLOC
frequencies (i.e., make the selected standby
frequency active).

190-00356-01 Rev K

3

KEYS AND KNOBS

Right-hand Keys and Knobs

R

D

m

c

E

The range key (RNG) allows you to select

the desired map scale. Press the up arrow side
of the key to zoom out or the down arrow
side to zoom in.

The direct-to key allows you to enter a

destination waypoint and establishes a direct
course to the selected destination.

The menu key (MENU) displays a context-

sensitive options list. The options list allows
you to make settings changes that relate to
the currently displayed page.

The clear key (CLR) is used to erase infor-

mation or cancel an entry. Press and hold this
key to immediately display the Default NAV
Page.

The enter key (ENT) is used to approve an

operation or complete data entry. It is also
used to confirm information, such as during
power on.

Range (map scale)

Direct-To

Clear

Large right knob

Menu

Enter

Small right knob

t

r

4

The large right knob is used to select

between the various page groups: NAV, WPT,
AUX or NRST. With the on-screen cursor
enabled, the large right knob allows you to
move the cursor about the page.

The small right knob is used to select

between the various pages within one of the
groups listed above. Press this knob momen­tarily to display the on-screen cursor. The
cursor allows you to enter data and/or make a
selection from a list of options.

190-00356-01 Rev K

KEYS

Bottom Row Keys

GPS 400W

GNC 420W

GNS 430W

N

C

O

As a Suspend (SUSP) key, it is used to

The nearest (NRST) key (GPS 400W

and GNC 420W only) displays the nearest
airports page. Then, turning the small right
knob steps through the NRST pages.

In the GNS 430W, the CDI key is used to

toggle which navigation source (GPS or
VLOC) provides output to an external HSI or
CDI.

The omni-bearing selector (OBS) key
is used for two functions: to activate OBS
selection and as a suspend key.

select manual or automatic sequencing of
waypoints. Pressing this key selects SUSP
mode, which retains the current “active to”
waypoint as your navigation reference even
after passing the waypoint (i.e., prevents
sequencing to the next waypoint). Press­ing the OBS key again returns to normal
operation, with automatic sequencing of
waypoints.

F

P

The flight plan (FPL) key allows you to

create, edit, activate and invert flight plans,
as well as access approaches, departures and
arrivals. A closest-point-to-flight-plan feature
is also available from the flight plan key.

The procedures (PROC) key allows you

to select approaches, departures and arriv­als from your active flight plan. When using
a flight plan, available procedures for your
departure and/or arrival airport are offered
automatically. Otherwise, you may select the
desired airport, then the desired procedure.

Whenever OBS mode is selected, you may

set the desired course to/from a waypoint
using the OBS Page, or an external OBS
selector on your HSI or CDI.

M

The message (MSG) key is used to view
system messages, important warnings, and
requirements.

190-00356-01 Rev K

5

POWER ON

Powering on the Unit

1. Turn the COM power/volume knob clockwise to
turn the unit on and set the desired radio volume.

2. The Main and GPS software version page appears
briefly, followed by land and terrain database pages,
as the unit conducts self-tests to ensure proper
operation.

3. Once the self-test concludes, database confirma­tion pages are displayed, showing the effective and
expiration dates of the databases on the NavData®
card. Press the ENT key to acknowledge the last
database page and proceed to the instrument panel
self-test page. There may be more self-test screens
depending on optional equipment installed in your
aircraft.

4. The instrument panel self-test page allows you
to verify that the unit is communicating properly
with in-panel instruments. Compare on-screen
indications with the information depicted on
connected instruments, such as the CDI, HSI, RMI
and/or external annunciators. Once you have veri­fied proper operation, turn the large right knob
to select "Set Full Fuel?", "Go To Checklist", or
"OK?" (to display the Satellite Status Page), and
then press the ENT key.

5. When the GPS receiver has acquired a sufficient
number of satellites to determine a position, the
Map Page will automatically appear showing your
present position.

6

Power-up Sequence

190-00356-01 Rev K