Garmin Cessna Caravan G1000 User manual

190-00907-00 September 2008 Revision B
G1000 SYSTEM MAINTENANCE MANUAL
STANDARD PISTON/TURBOPROP AIRCRAFT

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G1000 System Maintenance Manual Page A-1
190-00907-00 Rev. B
© 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
DOCUMENT PAGINATION
Section Pages
Table of Contents i to x
Section 1 1-1 to 1-2
Section 2 2-1 to 2-8
Section 3 3-1 to 3-6
Section 4 4-1 to 4-6
Section 5 5-1 to 5-82
Section 6 6-1 to 6-8
Section 7 7-1 to 7-46
Section 8 8-1 to 8-4
Section 9 9-1 to 9-6
Section 10 10-1 to 10-14
Appendix A A-1 to A-36

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Rev. B 190-00903-00
RECORD OF REVISIONS
Revision Date Section Page Description
A 5/2/08 ---- ---- Intial Release
B 9/23/08 ---- Cover
Page
Added “Turboprop” to title page
--- A Added Rev. B to table of revisions, revised table
to accommodate more detail.
--- i Changed GDU software version to 9.0x.
1 1-1 Added "turboprop" after piston.
2 2-1 Added "turboprop" after piston.
4 4-4 Changed the wording on the SD card installation
procedure
5 --- Edited Section 5 in its entirety to bring
information up to vGDU 9.0x.
6-4 Item 6.12 GSA Replacement, added a caution
about making sure the GSA fits against the GSM
mount with no gaps before tightening the
mounting bolts to prevent pushing in the bushing
which would require GSM replacement.
6-5 Section 6.13 - corrected the bullet list numbering
6
6-6 Section 6.14 - corrected the section # references
in the install list #4, #5 & #10.
7 ----- Edited Section 7 in its entirety to bring
information up to vGDU 9.0x.
9 9-4 Section 9.8: Added a note stating that after sw
version 8.20 there is no need to backload GDU
software to check the backup caps for certain
aircraft.
10-1 Edited note and added new section 10.1,
Hardware and Software Compatibility Check.
10-10 Added new section 10.9 Installation of OEM
specific splash screen procedure.
10
10-12 Added new section 10.11, Generic SVS Loading
Procedure for GDU v9.0x and above.

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G1000 System Maintenance Manual Page i
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This manual reflects the operation and configuration of GDU v9.0x.
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. B 190-00907-00
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
G1000 software configuration 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
information for correct software versions/part numbers and procedures
for a specific aircraft model when returning an aircraft to service.
NOTE
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.). The only duplicate in the
prefix of any LRU pertains to the GDL 69(x) XM Satellite Receiver and
the GDL 90 GPS WAAS Receiver/UAT. The suffix will be added in that
situation.

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TABLE OF CONTENTS
SECTION 1—INTRODUCTION
1.1 Scope...........................................................................................................1-1
1.2 Manual Organization ....................................................................................1-1
SECTION 2—LRU DESCRIPTIONS
2.1 Displays (GDU 1xxx PFD/MFD)...................................................................2-1
2.2 GMA 1347(x) Audio Panel............................................................................2-2
2.3 GIA 63(x) Integrated Avionics Unit...............................................................2-2
2.4 GDC 74(x) Air Data Computer......................................................................2-3
2.5 GEA 71 Engine/Airframe Unit.......................................................................2-3
2.6 GTX 33(x) Transponder................................................................................2-4
2.7 GRS 77 Attitude, Heading, and Reference Unit (AHRS)..............................2-4
2.8 GMU 44 Magnetometer................................................................................2-5
2.9 GDL 69(x) Satellite Data Link Receiver........................................................2-5
2.10 GSA 8(x) AFCS Servo Actuator and GSM 85(A) Servo Gearbox ................2-6
2.11 GTP 59 OAT Probe......................................................................................2-6
2.12 GDL 90 GPS WAAS Receiver/UAT..............................................................2-7
2.13 GWX 68 Weather Radar...............................................................................2-7
2.14 GTA 82 Pitch Trim Adapter ..........................................................................2-8
SECTION 3—SYSTEM OVERVIEW
3.1 G1000 Flight Instrumentation.......................................................................3-2
3.2 G1000 Engine Indication System.................................................................3-3
3.3 G1000 Communication and Navigation System...........................................3-4
3.4 GFC 700 Autopilot........................................................................................3-5

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SECTION 4—CONFIGURATION MODE
4.1 Introduction...................................................................................................4-1
4.2 G1000 Operation..........................................................................................4-2
4.3 Configuration Page Groups and Pages........................................................4-2
4.4 Secure Digital (SD) Cards............................................................................4-4
4.5 'SET' and 'ACTIVE' Commands ...................................................................4-5
4.6 Configuration Status.....................................................................................4-6
4.7 Data Transmission Indicators.......................................................................4-6
SECTION 5—TROUBLESHOOTING
5.1 System Annunciations..................................................................................5-1
5.2 Messages and Annunciations ......................................................................5-9
5.3 System Setup Page (MFD Normal Mode)..................................................5-10
5.4 GDU Related Alerts and Problems.............................................................5-27
5.5 GMA 1347 Related Alerts and Problems....................................................5-40
5.6 GIA 63W Related Alerts and Problems......................................................5-43
5.7 GRS 77/GMU 44 Related Alerts and Problems..........................................5-52
5.8 GDC 74A Related Alerts and Problems .....................................................5-54
5.9 GDC 74A Field Calibration Utility ...............................................................5-55
5.10 GEA 71 Related Alerts and Problems........................................................5-62
5.11 GTX 33 Related Alerts and Problems ........................................................5-63
5.12 GDL 69/69A Related Alerts and Problems.................................................5-64
5.13 AFCS System Troubleshooting..................................................................5-66
5.14 Backplate Connectors ................................................................................5-78
SECTION 6—LRU REPLACEMENT PROCEDURES
6.1 Accessing LRUs...........................................................................................6-1
6.2 GDU Replacement .......................................................................................6-2
6.3 GMA Replacement.......................................................................................6-2
6.4 GIA Replacement.........................................................................................6-2
6.5 GRS Replacement........................................................................................6-3
6.6 GMU Replacement.......................................................................................6-3
6.7 GDC Replacement .......................................................................................6-3
6.8 GEA Replacement........................................................................................6-3
6.9 GTX Replacement........................................................................................6-4
6.10 GDL 69(x) Replacement...............................................................................6-4
6.11 GDL 90 Replacement...................................................................................6-4
6.12 GSA Replacement........................................................................................6-4
6.13 GSM Replacement.......................................................................................6-5
6.14 Configuration Module ...................................................................................6-6
6.15 GEA Backshell Thermocouple .....................................................................6-7

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SECTION 7—LRU SOFTWARE INSTALLATION AND TESTING
7.1 Introduction...................................................................................................7-1
7.2 GDU Software Installation and Testing .......................................................7-4
7.3 GIA Software Installation and Testing..........................................................7-7
7.4 GMA Software Installation and Testing......................................................7-13
7.5 GRS/GMU Software Installation and Testing...............................................7-8
7.6 GDC Software Installation and Testing ......................................................7-27
7.7 GEA Software Installation and Testing.......................................................7-29
7.8 GTX Software Installation and Testing ......................................................7-31
7.9 GDL Software Installation and Testing ......................................................7-31
7.10 GSA Software Installation and Testing ......................................................7-33
7.11 GWX Software Installation and Testing .....................................................7-37
7.12 GCU 476 Remote Keypad..........................................................................7-39
7.13 Optional Systems .......................................................................................7-41
SECTION 8—RETURN TO SERVICE TESTING
8.1 GPS Failure Test..........................................................................................8-2
8.2 GIA Failure Test ...........................................................................................8-3
8.3 GDU Failure Test .........................................................................................8-3
8.4 AHRS/Air Data Backup Path Test................................................................8-4
8.5 Flight Test.....................................................................................................8-4
8.6 VHF COM Tests...........................................................................................8-4
8.7 VOR/ILS Tests .............................................................................................8-4
8.8 Maintenance Records ..................................................................................8-4
SECTION 9—PERIODIC MAINTENANCE
9.1 Service Timer ...............................................................................................9-1
9.2 Maintenance Intervals ..................................................................................9-1
9.3 Recommended Tools ...................................................................................9-1
9.4 General Maintenance Procedures................................................................9-2
9.5 GFC Visual Inspection Procedure................................................................9-2
9.6 GSA Greasing Procedure.............................................................................9-3
9.7 GDC RVSM Altitude Inspection....................................................................9-3
9.8 Category B Long Term Power Interrupt Inspection......................................9-4

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SECTION 10—SYSTEM RECONFIGURATION
10.1 Hardware and Software Compatibility Check.............................................10-1
10.2 Configuration File Overview .......................................................................10-1
10.3 Initial Software and Configuration Overview...............................................10-3
10.4 G1000 Software and Configuration Upload................................................10-4
10.5 Final Configuration Items ...........................................................................10-6
10.6 Software/Configuration Troubleshooting....................................................10-7
10.7 System Communication Hierarchy.............................................................10-8
10.8 Aviation Databases ....................................................................................10-9
10.9 Installation Of OEM Specific Splash Screens ..........................................10-10
10.10 TAWS Configuration.................................................................................10-10
10.11 Terrain-Synthetic Vision (SVS) Configuration..........................................10-12
10.12 Jeppesen Databases................................................................................10-13
10.13 Miscellaneous G1000 Databases.............................................................10-14
10.14 Updating Garmin Databases....................................................................10-15
APPENDIX A—CONNECTOR PIN ASSIGNMENTS
A.1 GIA 63(x)............................................................................................................A-1
A.2 GDU 1xxx.........................................................................................................A-12
A.3 GRS 77.............................................................................................................A-16
A.4 GMU 44............................................................................................................A-18
A.5 GDC 74(x)........................................................................................................A-19
A.6 GEA 7(x)...........................................................................................................A-21
A.7 GMA 1347(x)....................................................................................................A-25
A.8 GSA 8(x)...........................................................................................................A-29
A.9 GTA 82.............................................................................................................A-29
A.10 GTX 33(x).........................................................................................................A-31
A.11 GDL 69(x).........................................................................................................A-33
A.12 GWX 68............................................................................................................A-35

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FIGURES
2-1 GDU 1xxx PFD/MFD....................................................................................2-1
2-2 GMA 1347(x) Audio Panel............................................................................2-2
2-3 GIA 63(x) Integrated Avionics Unit...............................................................2-2
2-4 GDC 74(x) Air Data Computer......................................................................2-3
2-5 GEA 71 Engine/Airframe Unit.......................................................................2-3
2-6 GTX 33(x) Transponder................................................................................2-4
2-7 GRS 77 Attitude, Heading, and Reference Unit (AHRS)..............................2-4
2-8 GMU 44 Magnetometer................................................................................2-5
2-9 GDL 69(x) Satellite Data Link Receiver........................................................2-5
2-10 GSA 8(x) Servo Actuator..............................................................................2-6
2-11 GTP 59 OAT Probe......................................................................................2-6
2-12 GDL 90 GPS WAAS Receiver/UAT..............................................................2-7
2-13 GWX 68 Weather Radar...............................................................................2-7
2-14 GTA 82 Pitch Trim Adapter ..........................................................................2-8
3-1 Basic G1000 System....................................................................................3-1
3-2 Basic G1000 Flight Instrumentation .............................................................3-2
3-3 Basic G1000 Engine Indication System .......................................................3-3
3-4 Basic G1000 Communication and Navigation System.................................3-4
3-5 Basic GFC 700 Autopilot System.................................................................3-5
4-1 System Status Page (Configuration Mode)..................................................4-1
4-2 G1000 Softkeys............................................................................................4-2
4-3 GDU Bezel SD Card Slots............................................................................4-4
4-4 SET and ACTIVE Softkeys and Columns.....................................................4-5
4-5 Configuration Status Prompts ......................................................................4-6
4-6 Data Transmission Indicators.......................................................................4-6
4-7 Loss Of Communication Indication...............................................................4-6
5-1 Typical Invalid Display Fields .......................................................................5-1
5-2 Additional Invalid Display Fields...................................................................5-2
5-3 Messages and Annunciations ......................................................................5-9
5-4 System Status Page (AUX Group).............................................................5-10
5-5 GDC 74A – PC Interface Cable..................................................................5-55
5-6 GDC 74A Field Calibration Utility, Main Page............................................5-56
5-7 Serial Pull-Down List ..................................................................................5-57
5-8 0 Feet Calibration Screen...........................................................................5-57
5-9 Calibration Failed Screen...........................................................................5-58
5-10 Program Calibration to Unit Screen............................................................5-59
5-11 Field Calibration Result Screen..................................................................5-59
5-12 Calibration Files Screen .............................................................................5-60
5-13 Example Post-Calibration E-mail................................................................5-61

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5-14 About Screen..............................................................................................5-61
5-15 AFCS Annunciation Field ...........................................................................5-66
5-16 GIA Backshell Connectors .........................................................................5-78
5-17 GEA 71 Backshell Connectors...................................................................5-79
5-18 GMA Backshell Connectors .......................................................................5-79
5-19 GTX 33 Backshell Connectors ...................................................................5-80
5-20 GDU Backshell Connector (P10001)..........................................................5-81
5-21 GRS Backshell Connector (P771)..............................................................5-81
5-22 GDC Backshell Connector (P741)..............................................................5-81
5-23 GDL 69A Backshell Connector (P691).......................................................5-81
5-24 GDL 90 Backshell Connectors ...................................................................5-82
5-25 GCU 476 Backshell Connector (P4751).....................................................5-83
5-26 GSA 81 Backshell Connector (P801).........................................................5-83
5-27 GTA 82 Backshell Connector (P821) .........................................................5-83
6-1 System Status Page (Configuration Mode)..................................................6-1
6-2 Configuration Module ...................................................................................6-6
6-3 GEA Backshell Thermocouple .....................................................................6-7
7-1 Non-WAAS (GIA 63) System Status Page...................................................7-2
7-2 WAAS (GIA 63) System Status Page...........................................................7-2
7-3 G1000 Normal Mode Check.........................................................................7-6
7-4 G1000 Reversionary Mode Check ...............................................................7-6
7-5 AUX-GPS Status Page (example)..............................................................7-11
7-6 Marker Beacon Symbology ........................................................................7-14
7-7 Pitch/Roll Offset..........................................................................................7-17
7-8 Magnetometer Calibration..........................................................................7-18
7-9 Engine Run-Up...........................................................................................7-23
7-10 Magnetometer Interference........................................................................7-25
8-1 System Status Page (Configuration Mode)..................................................8-1
9-1 Total Time in Service....................................................................................9-1
9-2 System Upload Page....................................................................................9-5
9-3 Upload 'Complete' Window...........................................................................9-5
9-4 BKUP CAPS Checkbox on GDU Test Page.................................................9-5

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TABLES
4-1 Configuration Page Groups (example only) .................................................4-3
7-1 GRS 77/GMU 44 Calibration......................................................................7-17
9-1 GDC 74B RVSM Altitude Inspection Criteria................................................9-3

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190-00907-00 Rev. B
SECTION 1
INTRODUCTION
This manual provides maintenance information for the Garmin G1000 Avionics System configured in a
piston or turboprop aircraft.
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). The G1000 can be configured using two or three displays. This manual
describes a two display system.
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―LRU Descriptions
This section describes each G1000 LRU.
Section 3―System Overview
This section gives give an overview of the G1000 System.
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
LRU DESCRIPTIONS
This section describes the Line Replaceable Units (LRUs) that could be configured in a G1000 for piston
and turboprop aircraft. Not all of the LRUs described in this section are necessarily standard equipment,
some are optional depending on the specific model of aircraft. Refer to OEM maintenance documentation
for the exact quantity of LRUs used in a specific installation.
•GDU 1xxx Multi Function Display (MFD)
•GDU 1xxx Primary Flight Display (PFD)
•GMA 1347(x) Audio Panel with Marker Beacon Receiver
•GIA 63(x) Integrated Avionics Units (IAU)
•GDC 74(x) Air Data Computer (ADC)
•GEA 71 Engine/Airframe Unit
•GTX 33(x) Transponder
•GRS 77 Attitude and Heading Reference System (AHRS)
•GMU 44 Magnetometer
•GDL 69(x) Satellite Data Link Receiver
•GSA 8(x) AFCS Servo Actuator
•GSM 85(A) Servo Gearbox
•GTP 59 Temperature Probe
•GDL 90 GPS WAAS Receiver/UAT
•GWX 68 Weather Radar
•GTA 82 Trim Adapter
2.1 DISPLAYS (GDU 1xxx PFD and GDU 1xxx MFD)
Figure 2-1. GDU 1xxx PFD/MFD

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The GDU 1xxx is the most visible portion of the G1000. In a two display installation, one GDU is
configured as a Primary Flight Display (PFD), the other is configured as the Multi-Function Display
(MFD). The MFD displays navigation information and engine/airframe instrumentation. The PFD
displays primary flight information in place of traditional gyro systems. The displays communicate with
each other and with the GIA LRUs through a high-speed data bus (HSDB) Ethernet connection. The
GDUs also provide control for the GFC 700 Autopilot.
2.2 GMA 1347(x) AUDIO PANEL
Figure 2-2. GMA 1347(x) Audio Panel
The GMA 1347(x) integrates NAV/COM digital audio, intercom system and marker beacon controls.
The Audio Panel is typically installed between the MFD and PFD but can also be installed in dual-audio
panel applications (usually paired with a dual-PFD setup). The Audio Panel communicates with both
GIAs using RS-232 digital interface. The GMA 1347D model differs from the GMA 1347 in cabin and
intercom functionality.
2.3 GIA 63(x) INTEGRATED AVIONICS UNIT
Figure 2-3. GIA 63(x) Integrated Avionics Unit

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The GIA is the central ‘Integrated Avionics Unit’ (IAU) to the G1000 system. The GIA functions as a
main communications hub. The GIA contains the GPS receiver, VHF COM/NAV receivers, and system
integration microprocessors. The GIA communicates directly with the displays using a HSDB Ethernet
connection. Software and configuration settings are sent from the displays through the GIA to LRUs in
the system. The GIA 63W model contains a WAAS certified GPS receiver.
2.4 GDC 74(x) AIR DATA COMPUTER
Figure 2-4. GDC 74(x) Air Data Computer
The GDC 74(x) Air Data Computer compiles information from the pitot/static system and outside air
temperature (OAT) probe. The unit provides pressure altitude, airspeed, vertical speed, and OAT
information to the G1000 system. The GDC communicates with the GIAs, GDUs, and GRS LRUs using
an ARINC 429 digital interface. The GDC 74(A) model is a non-RVSM unit (reduced vertical separation
minima or minimum) and the GDC 74(B) is an RVSM capable unit.
2.5 GEA 71 ENGINE/AIRFRAME UNIT
Figure 2-5. GEA 71 Engine/Airframe Unit

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The GEA 71 is a microprocessor-based LRU that receives and processes signals from the engine and
airframe sensors. Sensors may include engine temperatures, oil temperature and pressure, fuel
measurement, airframe discrete inputs and other airframe inputs. The GEA communicates directly with
both GIAs using RS-485 digital interface. Software and configuration settings are received through RS-
485 digital interface with the GIA.
2.6 GTX 33(x) TRANSPONDER
Figure 2-6. GTX 33(x) Transponder
The GTX 33(x) is a mode-S transponder providing modes A, C, and S. Control and operation is directed
through the PFD. The transponder communicates with both GIAs through RS-232 digital interface in a
single transponder installation. In a dual transponder installation each transponder typically
communicates only with its on-side GIA. The GTX 33(D) model provides diversity functionality.
2.7 GRS 77 ATTITUDE, HEADING, AND REFERENCE UNIT (AHRS)
Figure 2-7. GRS 77 AHRS Unit