Garmin Cessna Caravan G1000 User manual

190-00903-00 May 2008 Rev. A
G1000 SYSTEM MAINTENANCE MANUAL
(LJ/VLJ AIRCRAFT)

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G1000 System Maintenance Manual Page A-1
190-00903-00 Rev. A
© Copyright 2008
Garmin Ltd. or its subsidiaries
All Rights Reserved
Except as expressly provided herein, no part of this manual may be reproduced, copied,
transmitted, disseminated, downloaded or stored in any storage medium, for any purpose without
the express prior written consent of Garmin. Garmin hereby grants permission to download a
single copy of this manual and of any revision to this manual onto a hard drive or other
electronic storage medium to be viewed and to print one copy of this manual or of any revision
hereto, provided that such electronic or printed copy of this manual or revision must contain the
complete text of this copyright notice and provided further that any unauthorized commercial
distribution of this manual or any revision hereto is strictly prohibited.
Garmin International, Inc.
1200 E. 151st Street
Olathe, KS 66062 USA
Telephone: [phone]
Aviation Panel-Mount Technical Support Line (Toll Free): 1-888-606-5482
www.garmin.com
Garmin Ltd. (Europe)
Liberty House, Bulls Copse Road
Hounsdown Business Park
Southampton, SO40 9RB, U.K.
p: 44/0870.8501241 f: 44/0870.8501251
RECORD OF REVISIONS
Revision Revision Date Description
A 5/7/08 Initial Release
DOCUMENT PAGINATION
Section Pages
Table of Contents i-xii
Section 1 1-1 — 1-2
Section 2 2-1 — 2-8
Section 3 3-1 — 3-12
Section 4 4-1 — 4-10
Section 5 5-1 — 5-130
Section 6 6-1 — 6-12
Section 7 7-1 — 7-34
Section 8 8-1 — 8-6
Section 9 9-1 — 9-14
Section 10 10-1 — 10-14
Appendix A A-1 — A-34

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This manual reflects the operation and configuration of GDU software version 9.00.
The following are general safety precautions that are not related to any specific procedure
and therefore do not appear elsewhere in this maintenance manual. These are
recommended precautions that personnel should understand and apply during the many
phases of maintenance and repair.
KEEP AWAY FROM LIVE CIRCUITS. Maintenance personnel shall observe all
safety regulations at all times. Turn off system power before making or breaking
electrical connections. Regard any exposed connector, terminal board, or circuit board as
a possible shock hazard. Components which retain a charge shall be discharged only
when such grounding does not result in equipment damage. If a test connection to
energized equipment is required, make the test equipment ground connection before
probing the voltage or signal to be tested.
DO NOT SERVICE ALONE. Personnel shall not under any circumstances reach into
or enter any enclosure for the purpose of servicing or adjusting the equipment without
immediate presence or assistance of another person capable of rendering aid.
INFORMATION SUBJECT TO EXPORT CONTROL LAWS
“This document may contain information which is subject to the Export Administration
Regulations (“EAR”) issued by the United States Department of Commerce (15 CFR,
Chapter VII Subchapter C) and which may not be exported, released or disclosed to
foreign nationals inside or outside the United States without first obtaining an export
license. The preceding statement is required to be included on any and all reproductions
in whole or in part of this manual.”

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Page ii G1000 System Maintenance Manual
Rev. A 190-00903-00
WARNING
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 the Garmin web
site at www.garmin.com/prop65.
CAUTION
The GDU 1xxx lamps contain mercury and must be recycled or
disposed of according to local, state, or federal laws. If you have
any questions or would like additional information, please refer to
our web site at the following website:
www.garmin.com/aboutGarmin/environment/disposal.jsp.
CAUTION
The GDU 1xxx lens is coated with a special anti-reflective coating
which is very sensitive to skin oils, waxes and abrasive cleaners.
CLEANERS CONTAINING AMMONIA WILL HARM THE
ANTI-REFLECTIVE COATING. It is very important to clean the
lens using a clean, lint-free cloth and an eyeglass lens cleaner that
is specified as safe for anti-reflective coatings.
NOTE
The content in this manual is nonspecific and is not associated to
any particular aircraft configuration. All display screen shots serve
as examples only.
NOTE
System software configuration and operation may differ between
different aircraft models. Procedures given in this manual are for
general reference only. Always refer to approved OEM aircraft
installation and/or maintenance data for correct software
versions/part numbers and procedures for a specific aircraft model
when returning an aircraft to service.
NOTE
At times, to more closely match the LRU nomenclature displayed
on the configuration pages, and where appropriate, only the prefix
of the LRU will be listed (i.e., GTX 33(x); GTX, etc.).

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TABLE OF CONTENTS
SECTION 1—INTRODUCTION
1.1 Scope..............................................................................................................1-1
1.2 Manual Organization .....................................................................................1-1
SECTION 2—SYSTEM OVERVIEW
2.1 G1000 Flight Instrumentation........................................................................2-1
2.2 Navigation and Communication Systems......................................................2-4
2.3 GFC 700 Interconnect....................................................................................2-5
2.4 GDU 1xxx Overview.....................................................................................2-6
2.4.1 GDU Communication....................................................................................2-7
SECTION 3—EQUIPMENT DESCRIPTION
3.1 Displays (MFD/PFD).....................................................................................3-1
3.1.1 GDU 1500......................................................................................................3-1
3.1.2 GDU 1040A...................................................................................................3-2
3.1.3 GDU 1240A...................................................................................................3-2
3.2 GMA 1347/1347D Audio Panel ....................................................................3-3
3.3 GIA 63/63W Integrated Avionics Unit..........................................................3-3
3.4 GRS 77 Attitude, Heading, and Reference Unit (AHRS)..............................3-4
3.5 GMU 44 Magnetometer.................................................................................3-4
3.6 GDC 74B Air Data Computer........................................................................3-5
3.7 GEA 71 Engine/Airframe Unit......................................................................3-5
3.8 GTX 33/33D Transponder.............................................................................3-6
3.9 GDL 69/69A Satellite Data Link Receiver....................................................3-6
3.10 GDL 90 GPS WAAS Receiver/UAT............................................................. 3-7
3.11 GSA 80/81 AFCS Servos/GSM 85(A) Servo Gearbox.................................3-7
3.12 GWX 68 Weather Radar................................................................................3-8
3.13 GTP 59 OAT Probe .......................................................................................3-8
3.14 GTX 33/33D Mode S Transponder................................................................3-9
3.15 GCU 475 MFD Control Unit.........................................................................3-9
3.16 GMC 715 AFCS Control Unit.....................................................................3-10
3.17 GSD 41 Data Concentrator.......................................................................... 3-10
3.17.1 GRC 10XM Remote Control.......................................................................3-10

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3.17.2 GRT 10XM Wireless Transceiver............................................................... 3-11
3.18 GCU 477......................................................................................................3-11
3.19 GSR 56/GDL 59 ..........................................................................................3-12
SECTION 4—CONFIGURATION MODE
4.1 Introduction....................................................................................................4-1
4.2 Configuration Page Groups and Pages ..........................................................4-2
4.2.1 User Interface.................................................................................................4-2
4.2.2 Softkeys..........................................................................................................4-2
4.3 Secure Digital (SD) Cards .............................................................................4-3
4.4 Configuration Files ........................................................................................ 4-5
4.4.1 Configuration File Retention.........................................................................4-5
4.5 'SET' and 'ACTIVE' Commands.................................................................... 4-8
4.5.1 'SET' and 'ACTIVE' Softkeys........................................................................ 4-8
4.6 Configuration Status ...................................................................................... 4-9
4.7 Data Transmission Indicators ........................................................................4-9
SECTION 5—TROUBLESHOOTING
5.1 Troubleshooting Methods..............................................................................5-1
5.1.1 Visual Hardware Inspection...........................................................................5-1
5.1.2 LRU Failure Annunciations........................................................................... 5-1
5.1.3 System Status Page Failure Indications ........................................................5-8
5.1.4 Data Path Failure Messages...........................................................................5-8
5.1.5 Configuration Page Data Path Indicators.......................................................5-9
5.1.6 Advisory Messages......................................................................................5-36
5.1.7 Common Problems.......................................................................................5-68
5.1.8 Using Configuration Pages in Troubleshooting...........................................5-77
5.1.9 Troubleshooting the GFC 700 Autopilot...................................................5-102
5.2 Calibration Procedures............................................................................... 5-114
5.2.1 GDC 74B Calibration Procedure............................................................... 5-114
5.2.2 GEA 71 Standby Battery HSCM Calibration Procedure...........................5-120
5.3 Backplate Connectors ................................................................................ 5-125

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SECTION 6—REPLACEMENT PROCEDURES
6.1 GDU 1xxx......................................................................................................6-2
6.2 GMA 1347D ..................................................................................................6-2
6.3 GIA 63/63W...................................................................................................6-2
6.4 GRS 77...........................................................................................................6-3
6.5 GMU 44.........................................................................................................6-3
6.6 GDC 74B ....................................................................................................... 6-3
6.7 GEA 71 ..........................................................................................................6-4
6.8 GTX 33 ..........................................................................................................6-4
6.9 GDL 69/69A ..................................................................................................6-5
6.10 GDL 90 ..........................................................................................................6-5
6.11 GSA 81...........................................................................................................6-5
6.12 GSM 85(A) ....................................................................................................6-6
6.13 GSD 41...........................................................................................................6-6
6.14 GRT 10...........................................................................................................6-6
6.15 GDL 59/GSR 56 ............................................................................................6-7
6.16 GCU 475/477................................................................................................. 6-7
6.17 GMC 710/715 ................................................................................................6-7
6.18 GWX 68......................................................................................................... 6-7
6.19 GTA 82 ..........................................................................................................6-8
6.20 Configuration Module....................................................................................6-9
6.21 GEA 71 Backplate Thermocouple...............................................................6-10
SECTION 7—SOFTWARE INSTALLATION AND TESTING
7.1 Upload Overview...........................................................................................7-1
7.1.1 System Upload Page Softkeys....................................................................... 7-2
7.1.2 GDU 1xxx......................................................................................................7-2
7.1.3 GIA 63W........................................................................................................7-4
7.1.4 GMA 1347D ..................................................................................................7-7
7.1.5 GRS 77/GMU 44 ...........................................................................................7-9
7.1.6 GDC 74B ..................................................................................................... 7-20
7.1.7 GEA 71 ........................................................................................................7-23
7.1.8 GTX 33/33D ................................................................................................7-24
7.1.9 GDL 69A ..................................................................................................... 7-25
7.1.10 GSA 80/81 ...................................................................................................7-26
7.1.11 GCU 475......................................................................................................7-30

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7.1.12 GMC 710 .....................................................................................................7-31
7.1.13 GWX 68.......................................................................................................7-32
SECTION 8—RETURN TO SERVICE TESTING
8.1 WAAS GPS Test............................................................................................8-2
8.2 GIA Test.........................................................................................................8-3
8.3 Display Test................................................................................................... 8-4
8.4 AHRS/Air Data Backup Path Test.................................................................8-5
8.5 Flight Test......................................................................................................8-5
8.6 VHF COM Tests............................................................................................ 8-5
8.7 VOR/ILS Tests...............................................................................................8-6
8.8 Maintenance Records.....................................................................................8-6
SECTION 9—PERIODIC MAINTENANCE
9.1 Service Timer.................................................................................................9-1
9.2 Maintenance Intervals....................................................................................9-1
9.3 Recommended Tools .....................................................................................9-2
9.4 General Maintenance Procedures ..................................................................9-2
9.5 GFC 700 Visual Inspection Procedure ..........................................................9-3
9.6 GSA 809(x) Greasing Procedure................................................................... 9-3
9.7 GSM Slip Clutch Checking and Adjustment Procedure................................ 9-4
9.8 GSM 85(A) Servo Gearbox Semi-Automated Slip Clutch Test....................9-4
9.8.1 Abnormal Test Message Prompts..................................................................9-9
9.9 GDC 74B RVSM Altitude Inspection .........................................................9-11
9.10 Category B Long Term Power Interrupt Inspection....................................9-11
SECTION 10—SYSTEM RECONFIGURATION
10.1 MFD & PFD Upload Procedure ..................................................................10-1
10.2 Initial System Software Upload...................................................................10-2
10.3 Software Load Confirmation .......................................................................10-2
10.4 Final Configuration Items............................................................................10-4
10.4.1 Aircraft Registration Number Entry............................................................10-4
10.5 Software/Configuration Troubleshooting....................................................10-6
10.6 System Communication Hierarchy..............................................................10-7
10.7 Aviation Database........................................................................................ 10-8
10.8 TAWS Configuration...................................................................................10-9
10.9 ChartView Configuration ..........................................................................10-10

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10.10 SD Card Use ..............................................................................................10-12
10.10.1 Jeppesen Database .....................................................................................10-12
10.10.2 Miscellaneous Databases...........................................................................10-12
10.11 Updating Garmin Databases......................................................................10-13
APPENDIX A—CONNECTOR PIN ASSIGNMENTS
A.1 P601 (COM).................................................................................................. A-1
A.2 P602 (VOR/ILS)........................................................................................... A-3
A.3 P603 (MAIN/SERIAL)................................................................................. A-5
A.4 P604 (MAIN DISCRETE)............................................................................ A-7
A.5 P605 (I/O #1) ................................................................................................A-8
A.6 P606 (I/O #2) ..............................................................................................A-10
A.7 P10001 (GDU 1xxx)................................................................................... A-12
A.8 P771 (GRS 77)............................................................................................ A-14
A.9 P441 (GNU 44)........................................................................................... A-15
A.10 P741 (GDC 74A) ........................................................................................ A-16
A.11 P701 (GEA 71) ........................................................................................... A-18
A.12 P702 ............................................................................................................ A-20
A.13 GMA 1347D (P3471) ................................................................................. A-22
A.14 P3472 .......................................................................................................... A-24
A.15 P3301 (GTX 33) ......................................................................................... A-26
A.16 GDL 69/69A (P691) ................................................................................... A-28
A.17 GSA 81 (P801)............................................................................................ A-30
A.18 P411 (GSD 41)............................................................................................ A-31
A.19 P412 (GSD 41)............................................................................................ A-33

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FIGURES
2-1 AHRS Block Diagram ...................................................................................2-1
2-2 Top-Level Interconnect Block Diagram........................................................2-2
2-3 Flight Instrumentation Data Paths .................................................................2-3
2-4 G1000 Navigation/Communication Data Paths............................................. 2-4
2-5 GFC 700 Autopilot Interconnect Block Diagram..........................................2-5
2-6 Three Display Installation Example .............................................................. 2-6
3-1 GDU 1500 Display ........................................................................................3-1
3-2 GDU 1040A Display......................................................................................3-2
3-3 GDU 1240A Display......................................................................................3-2
3-4 GMA 1347D Audio Panel ............................................................................. 3-3
3-5 GIA 63W Integrated Avionics Unit...............................................................3-3
3-6 GRS 77 AHRS Unit.......................................................................................3-4
3-7 GMU 44 Magnetometer.................................................................................3-4
3-8 GDC 74B Air Data Computer........................................................................3-5
3-9 GEA 71 Engine/Airframe Unit......................................................................3-5
3-10 GDL 69/69A Satellite Data Link Receiver....................................................3-6
3-11 GDL 90 Universal Access Transceiver/GPS Receiver..................................3-6
3-12 GSA 80 Servo................................................................................................3-7
3-13 GWX 68 Weather Radar................................................................................3-7
3-14 GTP 59 OAT Probe .......................................................................................3-8
3-15 GTX 33/33D Transponder.............................................................................3-8
3-16 GCU 475 MFD Control Unit.........................................................................3-9
3-17 GMA 715 AFCS Control Unit.......................................................................3-9
3-18 GSD 41 Data Concentrator.......................................................................... 3-10
3-19 GRT 10 Remote Controller/GRC 10 Wireless Transceiver ........................ 3-10
3-20 GCU 477 Remote Controller.......................................................................3-11
3-21 GDL 59 System Level Block Diagram........................................................3-12
4-1 System Status Page (Configuration Mode)....................................................4-1
4-2 Softkeys..........................................................................................................4-2
4-3 GDU 1xxx Bezel SD Card Slots....................................................................4-3
4-4 GRS/GDC Configuration File Storage (3 Display).......................................4-6
4-5 System Configuration File Storage (3 Display).............................................4-7
4-6 SET and ACTIVE Softkeys and Columns.....................................................4-8
4-7 Configuration Status Prompts........................................................................4-9
4-8 Data Transmission Indicators ........................................................................4-9

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4-9 Loss Of Communication................................................................................4-9
5-1 LRU Failure Annunciations........................................................................... 5-1
5-2 System Status Page (AUX Group).................................................................5-8
5-3 Main RS-232/ARINC 429 Configuration Page............................................. 5-9
5-4 GIA RS-232/ARINC 429 Configuration Page ............................................5-18
5-5 GIA RS-485 Configuration Page.................................................................5-30
5-6 Advisory Messages......................................................................................5-36
5-7 GDL 69 Configuration Page........................................................................5-75
5-8 GMA Configuration Page............................................................................5-78
5-9 AHRS/Air Data Input Configuration Page.................................................. 5-81
5-10 Engine Data Page.........................................................................................5-82
5-11 GEA Status Page..........................................................................................5-84
5-12 GEA Configuration Page.............................................................................5-85
5-13 GDU Status Page .........................................................................................5-86
5-14 GDU Test Page............................................................................................5-89
5-15 Diagnostics Page.......................................................................................... 5-92
5-16 Serial/Ethernet I/O Page .............................................................................. 5-93
5-17 Alert Configuration Page.............................................................................5-94
5-18 Airframe Configuration Page.......................................................................5-94
5-19 RS-232/ARINC 429 Configuration Page.....................................................5-95
5-20 CAN/RS-485 Configuration Page................................................................5-96
5-21 GIA I/O Configuration Page........................................................................5-97
5-22 COM Setup Page..........................................................................................5-98
5-23 GIA Status Page...........................................................................................5-99
5-24 GFC Configuration Page............................................................................5-101
5-25 GFC Status Page........................................................................................5-102
5-26 GFC 700 Annunciation Field.....................................................................5-103
5-27 GDC 74B PC Interface Cable.................................................................... 5-114
5-28 GDC 74B Field Calibration Utility, Main Page ........................................5-115
5-29 Serial Port Pull-Down List......................................................................... 5-115
5-30 '0 Feet' Calibration Screen.........................................................................5-116
5-31 'Calibration Failed' Screen.........................................................................5-116
5-32 'Program Calibration to Unit' Screen.........................................................5-117
5-33 'Field Calibration Result' Screen................................................................5-117
5-34 Calibration Files Screen.............................................................................5-118
5-35 Post-Calibration Email Example ...............................................................5-119
5-36 The 'About' Screen.....................................................................................5-119
5-37 AUX-System Status Page.......................................................................... 5-120
5-38 HSCM Offset Tool User Interface Display ...............................................5-121

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5-39 Configuration Upload Page .......................................................................5-122
5-40 HSCM Offset Tool User Interface Display ...............................................5-123
5-41 Post-Calibration Email Example ...............................................................5-124
5-42 GIA 63W Backplate Connectors ...............................................................5-125
5-43 GEA 71 Backplate Connectors.................................................................. 5-126
5-44 GSD 41 Keyplate Information...................................................................5-126
5-45 GMA 1347D Backplate Connectors.......................................................... 5-126
5-46 GTX 33/33D Backplate Connectors.......................................................... 5-127
5-47 GDU 1xxx Backplate Connector (P10001) ...............................................5-127
5-48 GRS 77 Backplate Connector (P771)........................................................ 5-127
5-49 GDC 74B Backplate Connector (P741).....................................................5-127
5-50 GDL 69A Backplate Connector (P691).....................................................5-128
5-51 GCU 475 Backplate Connector (P4751) ...................................................5-128
5-52 GMC 710 Backplate Connector (P7101)................................................... 5-128
5-53 GWX 68 Backplate Connector (P400) ......................................................5-128
5-54 GSD 41 Backplate Connector (P411)........................................................5-128
5-55 GSD 41 Backplate Connector (P412)........................................................5-129
6-1 System Status Page (Configuration Mode)....................................................6-1
6-2 Configuration Module....................................................................................6-9
6-3 GEA 71 Backplate Thermocouple...............................................................6-10
7-1 AUX-GPS Status Page (example) .................................................................7-5
7-2 Marker Beacon Symbology ........................................................................... 7-9
7-3 Pitch/Roll Offset ..........................................................................................7-12
7-4 Magnetometer Calibration...........................................................................7-13
7-5 Engine Run-Up ............................................................................................7-16
7-6 Magnetometer Interference..........................................................................7-18
8-1 System Status Page (Configuration Mode)....................................................8-1
9-1 Total Time in Service ....................................................................................9-1
9-2 GFC Status Page............................................................................................9-5
9-3 System Upload Page.................................................................................... 9-12
9-4 Upload 'Complete' Window.........................................................................9-12
9-5 BKUP CAPS Checkbox on GDU 1xxx Test Page ......................................9-13
10-1 System Status Page......................................................................................10-2
10-2 Transponder Configuration Page.................................................................10-4

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TABLES
4-1 Configuration Page Groups ...........................................................................4-4
5-1 LRU Failure Annunciations and Recommended Actions..............................5-2
5-2 AFCS Annunciations.................................................................................5-104
7-1 GRS 77/GMU 44 Calibration ......................................................................7-12
7-2 Magnetometer Interference Test Sequence..................................................7-19
9-1 Test Results.................................................................................................... 9-6
9-2 GDC 74B RVSM Altitude Inspection Criteria............................................9-11

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SECTION 1
INTRODUCTION
This manual provides maintenance information for the Garmin G1000 Integrated Flight Deck
installed and configured for VLJ and LJ (very light and light jet) aircraft. Troubleshooting, LRU
replacement, uploading and configuring software, and return to service testing procedures are
included.
1.1 SCOPE
This manual is general in scope and is intended to be used only as a guideline. Consult OEM
maintenance documentation for the most current and exact maintenance information for a
specific aircraft. This manual presumes familiarity with the basic operating procedures covered
in the G1000 Pilot's Guide and Cockpit Reference Guide (CRG).
1.2 MANUAL ORGANIZATION
The following is a brief description of each section in the manual.
Section 1―Introduction
This section discusses the scope of the manual content and describes manual organization.
Section 2―System Overview
This section gives give an overview of the G1000 System.
Section 3―LRU Descriptions
This section describes each G1000 LRU.
Section 4―Configuration Mode
This section explains the configuration mode and the role it plays in troubleshooting. It also
contains limited user interface information.
Section 5―Troubleshooting
This section contains troubleshooting procedures which can help isolate a defective LRU.
Section 6―Replacement Procedures
This section lists procedures needed to replace a defective LRU.
Section 7―LRU Software Installation and Testing
This section explains how to install, configure, and test software for a replacement LRU.
Section 8―Return To Service Testing
This section describes return to service tests.
Section 9―Periodic Maintenance
This section contains periodic maintenance procedures.

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Section 10―System Reconfiguration
This section explains how to completely reconfigure the system should it become necessary.
Appendix A―Connector Pin Assignments
This appendix illustrates and lists the names of G1000 connector pins.

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SECTION 2
SYSTEM OVERVIEW
This section describes the major subsystems of the G1000. Because G1000 configurations vary
depending on specific aircraft, this section is only a guideline. Refer to the OEM maintenance
documentation for aircraft specific system information.
2.1 G1000 FLIGHT INSTRUMENTATION
The GRS 77 AHRS, GDC 74B Air Data Computer, and GMU 44 Magnetometer supply the
G1000 with flight instrumentation data. The data consists of aircraft attitude, heading, altitude,
airspeed, vertical speed, and outside air temperature information, all displayed on the PFD (the
same data is displayed on the MFD in reversionary mode). Data outputs from the GRS 77 and
GDC 74B are sent directly to the PFD via ARINC 429. Additional communications paths
connect the GRS and GDC 74B to GIA 63W units providing quadruple redundant capability.
The GRS 77 receives GPS data from both GIAs, airspeed data from the GDC 74B, and magnetic
heading from the GMU. Using these three external sources, combined with internal sensor data,
the GRS accurately calculates aircraft attitude and heading (Figure 2-1).
In addition to using internal sensors, the GRS 77 uses GPS information, magnetic field data and
air data to assist in attitude/heading calculations. In normal mode, the GRS 77 relies upon GPS
and magnetic field measurements. If either of these external measurements is unavailable or
invalid, the GRS 77 uses air data information for attitude determination. Four GRS 77 modes of
operation are available and depend upon the combination of available sensor inputs. Loss of air
data, GPS, or magnetometer sensor inputs is communicated to the pilot by message advisory
alerts.
Figure 2-1. GRS 77 Block Diagram

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Figure 2-2 shows a top-level G1000 interconnect block diagram.
NOTE
The block diagrams shown in this section are not aircraft specific. Refer to
the OEM maintenance documentation for aircraft specific diagrams.
Figure 2-2. G1000 Top-Level Interconnect Block Diagram

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Figure 2-3 shows a G1000 flight instruments block diagram.
Figure 2-3. G1000 Flight Instrumentation Data Paths

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2.2 NAVIGATION AND COMMUNICATION SYSTEMS
The GIA 63W LRUs contain the VHF COM, VHF NAV, and WAAS GPS receivers. COM and
NAV digital audio is sent to the GMA 1347D Audio Panel. GPS data is sent to the GRS 77 and
both displays for processing. The GTX 33 and GTX 33D Mode S Transponders communicate
with their respective GIA. Transponder data is sent from the GIA to the PFD. The GMA 1347D
Audio Panel controls audio selections and the reversionary mode.
Figure 2-4. G1000 Navigation/Communication Data Paths