Garmin Diamond DA40 User manual

190-00303-03 January 2007 Revision 6
G1000 System
Maintenance Manual
Diamond DA 40

Page A G1000/DA40 System Maintenance Manual
Revision 6 190-00303-03
© Copyright 2007
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]
www.garmin.com
Garmin (Europe) Ltd.
Unit 5, The Quadrangle
Abbey Park Industrial Estate
Romsey, SO51 9DL U.K.
Telephone: [phone]
RECORD OF REVISIONS
Revision Revision Date Description ECO #
1 06/04/04 Experimental Release ------
26/17/04 Update for STC 26291
36/21/04 Update AW Limitations, Add Document Pagination
Table.
26344
48/24/04 Update for new GTX 33 SW 27110
5 9/3/04 Update for optional KAP 140 AFCS 27244
6 1/25/07 Update GDC Testing Process 42752
DOCUMENT PAGINATION
Section Pagination
Table of Contents i – vi
Section 1 1-1 – 1-4
Section 2 2-1 – 2-26
Section 3 3-1 – 3-12
Section 4 4-1 – 4-12
Section 5 5-1 – 5-24
Section 6 6-1 – 6-8
Section 7 7-1 – 7-34
Section 8 8-1 – 8-4
Appendix A A-1 – A-6
Appendix B B-1 – B-16

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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 of the United
States without first obtaining an export license. A violation of the EAR may be subject to a penalty of up
to 10 years imprisonment and a fine of up to $1,000,000 under Section 2410 of the Export Administration
Act of 1979. Include this notice with any reproduced portion of this document.
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 web site at www.garmin.com/prop65.
The GDU 1040s use a lens coated with a special anti-reflective coating that 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.
All G1000 screen shots used in this document are current at the time of publication. Screen shots are
intended to provide visual reference only. All information depicted in screen shots, including software
file names, versions and part numbers, is subject to change and may not be up to date.
CAUTION
WARNING
CAUTION

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TABLE OF CONTENTS
PARAGRAPH PAGE
1 INTRODUCTION
1.1 CONTENT,SCOPE,PURPOSE ...........................................................................................................1-1
1.2 ORGANIZATION ..............................................................................................................................1-1
1.3 DEFINITIONS/ABBREVIATIONS.......................................................................................................1-2
1.4 REFERENCE PUBLICATIONS............................................................................................................1-3
1.5 DISTRIBUTION ................................................................................................................................1-3
2 SYSTEM DESCRIPTION
2.1 EQUIPMENT DESCRIPTIONS............................................................................................................2-1
2.2 EQUIPMENT LOCATIONS ................................................................................................................2-8
2.3 REMOTE AVIONICS ENCLOSURE ....................................................................................................2-9
2.4 ELECTRICAL POWER DISTRIBUTION ............................................................................................2-11
2.5 LIGHTNING STRIKE PROTECTION .................................................................................................2-12
2.6 SPIDER GROUNDS.......................................................................................................................2-16
2.7 SENSOR INSTALLATIONS ..............................................................................................................2-17
2.8 G1000 SYSTEM COMMUNICATIONS .............................................................................................2-23
3 G1000 CONTROL & OPERATION
3.1 USER INTERFACE............................................................................................................................3-2
3.2 G1000 NORMAL MODE ..................................................................................................................3-3
3.3 REVERSIONARY MODE...................................................................................................................3-4
3.4 CONFIGURATION MODE OVERVIEW ..............................................................................................3-5
3.5 CONFIGURATION MODE NAVIGATION .........................................................................................3-11
4 G1000 CONTINUED AIRWORTHINESS
4.1 AIRWORTHINESS LIMITATIONS ......................................................................................................4-1
4.2 SERVICING INFORMATION..............................................................................................................4-1
4.3 ON CONDITION SERVICING ............................................................................................................4-1
4.4 MAINTENANCE REQUIREMENTS ....................................................................................................4-3
4.5 1000 HOUR INSPECTION.................................................................................................................4-5
4.6 ELECTRICAL BONDING TEST..........................................................................................................4-7
4.7 FUEL TANK PROBE RE-CALIBRATION............................................................................................4-8
4.8 GRS 77 EARTH MAGNETIC FIELD UPDATES................................................................................4-11
5 TROUBLESHOOTING
5.1 G1000 ALERTING SYSTEM .............................................................................................................5-2
5.2 SYSTEM ANNUNCIATIONS ..............................................................................................................5-4
5.3 DA 40-SPECIFIC ALERTS................................................................................................................5-8
5.4 GDU 1040 TROUBLESHOOTING .....................................................................................................5-9
5.5 GDU 1040 ALERTS ........................................................................................................................5-9
5.6 GMA ALERTS...............................................................................................................................5-12
5.7 GIA 63 TROUBLESHOOTING.........................................................................................................5-13
5.8 GIA ALERT MESSAGES ................................................................................................................5-14
5.9 GEA TROUBLESHOOTING ............................................................................................................5-19
5.10 GTX TROUBLESHOOTING ...........................................................................................................5-20
5.11 GRS 77/GMU 44 TROUBLESHOOTING........................................................................................5-21
5.12 GDC 74A TROUBLESHOOTING ...................................................................................................5-23
6 G1000 EQUIPMENT REMOVAL & REPLACEMENT
6.1 GDU 1040 MFD &PFD.................................................................................................................6-2
6.2 GMA 1347 AUDIO PANEL..............................................................................................................6-2
6.3 GIA 63 INTEGRATED AVIONICS UNITS ..........................................................................................6-3

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6.4 GEA 71 ENGINE/AIRFRAME UNIT .................................................................................................6-3
6.5 GTX 33 TRANSPONDER .................................................................................................................6-4
6.6 GDC 74A AIR DATA COMPUTER ...................................................................................................6-4
6.7 GTP 59 OAT PROBE ......................................................................................................................6-4
6.8 GRS 77 AHRS ...............................................................................................................................6-5
6.9 GMU 44 MAGNETOMETER.............................................................................................................6-5
6.10 CONFIGURATION MODULE REMOVAL &REPLACEMENT .............................................................6-6
6.11 GEA 71 BACKSHELL THERMOCOUPLE REMOVAL &REPLACEMENT...........................................6-7
7 G1000 EQUIPMENT CONFIGURATION & TESTING
7.1 GDU 1040 MFD &PFD.................................................................................................................7-1
7.2 GMA 1347 AUDIO PANEL..............................................................................................................7-5
7.3 GIA 63 INTEGRATED AVIONICS UNIT............................................................................................7-8
7.4 GEA 71 ENGINE/AIRFRAME UNIT ...............................................................................................7-14
7.5 GTX 33 TRANSPONDER ...............................................................................................................7-17
7.6 GDC 74A AIR DATA COMPUTER .................................................................................................7-21
7.7 GRS 77 AHRS /GMU 44 MAGNETOMETER................................................................................7-25
7.8 SOFTWARE/CONFIGURATION TROUBLESHOOTING ......................................................................7-34
8 SYSTEM RETURN TO SERVICE PROCEDURE
8.1 GPS FAILURE TEST ........................................................................................................................8-1
8.2 GIA FAILURE TEST ........................................................................................................................8-2
8.3 DISPLAY FAILURE TEST .................................................................................................................8-2
8.4 AHRS/ADC BACKUP PATH TEST ..................................................................................................8-3
8.5 FLIGHT TEST ..................................................................................................................................8-4
8.6 MAINTENANCE RECORDS...............................................................................................................8-4
APPENDIX A INSTALLATION DATA
A.1 G1000 EQUIPMENT LIST ..............................................................................................................A-1
A.2 ADDITIONAL EQUIPMENT REQUIRED........................................................................................... A-2
A.3 OPTIONAL EQUIPMENT ................................................................................................................A-2
A.4 PARTS LIST................................................................................................................................... A-3
A.5 WEIGHT &BALANCE ...................................................................................................................A-5
APPENDIX B G1000 SOFTWARE/CONFIGURATION PROCEDURE
B.1 SYSTEM POWER UP...................................................................................................................... B-2
B.2 MFD &PFD SOFTWARE LOAD.................................................................................................... B-3
B.3 INITIAL G1000 CONFIGURATION ................................................................................................. B-4
B.4 GIA SOFTWARE LOAD ................................................................................................................. B-5
B.5 GIA CONFIGURATION .................................................................................................................. B-7
B.6 FINAL LRU SOFTWARE LOAD ..................................................................................................... B-8
B.7 FINAL LRU CONFIGURATION .................................................................................................... B-14
B.8 SOFTWARE LOAD CONFIRMATION............................................................................................. B-15
B.9 AVIATION DATABASE LOADING ................................................................................................ B-16
B.10 FINAL SYSTEM TESTING ............................................................................................................ B-16

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LIST OF ILLUSTRATIONS
FIGURE PAGE
Figure 2-1. G1000 / DA 40 Panel Installation ..........................................................................................2-2
Figure 2-2. DA40 Panel (Rear View) .......................................................................................................2-4
Figure 2-3. GTP 59 OAT Probe................................................................................................................2-5
Figure 2-4. GRS 77 Mount .......................................................................................................................2-6
Figure 2-5. GMU 44 Installation...............................................................................................................2-7
Figure 2-6. G1000 in DA 40 Equipment Locations..................................................................................2-8
Figure 2-7. Remote Avionics Enclosure...................................................................................................2-9
Figure 2-8. G1000/DA40 Electrical Distribution....................................................................................2-11
Figure 2-9. TVS & Fuse Installation.......................................................................................................2-12
Figure 2-10. Lightning Protection Components .....................................................................................2-13
Figure 2-11. Component Plate Dimensions ............................................................................................2-13
Figure 2-12. Component Wiring Diagram..............................................................................................2-14
Figure 2-13. SPIDER Ground Installation..............................................................................................2-16
Figure 2-14. MAP Sensor .......................................................................................................................2-17
Figure 2-15. Oil Pressure Sensor ............................................................................................................2-17
Figure 2-16. Oil Temperature Sensor .....................................................................................................2-18
Figure 2-17. Fuel Pressure Sensor ..........................................................................................................2-18
Figure 2-18. Tachometer Sensor.............................................................................................................2-19
Figure 2-19. Fuel Flow Sensor & Fire Sleeve ........................................................................................2-19
Figure 2-20. Fuel Flow Assembled.........................................................................................................2-20
Figure 2-21. Fuel Flow Bracket ..............................................................................................................2-20
Figure 2-22. CHT Probe .........................................................................................................................2-21
Figure 2-23. EGT Probe..........................................................................................................................2-21
Figure 2-24. Alternator Current Sensor Installation ...............................................................................2-22
Figure 2-25. Flight Instrumentation Interface.........................................................................................2-23
Figure 2-26. G1000 Engine/Airframe Interface......................................................................................2-24
Figure 2-27. G1000 Navigation/Communications..................................................................................2-25
Figure 3-1. GDU 1040 Control Interface..................................................................................................3-1
Figure 3-2. GMA 1347 Controls...............................................................................................................3-1
Figure 3-3. G1000 Softkeys......................................................................................................................3-2
Figure 3-4. Normal Mode .........................................................................................................................3-3
Figure 3-5. MFD Failure Mode.................................................................................................................3-4
Figure 3-6. PFD Failure Mode..................................................................................................................3-4
Figure 3-7. G1000 LRU Configuration File Storage ................................................................................3-7
Figure 3-8. GRS/GDC Configuration Settings Storage ............................................................................3-8
Figure 3-9. SET>ACTV Diagram.............................................................................................................3-9
Figure 3-10. Loss of Communication .....................................................................................................3-10
Figure 3-11. Configuration Status...........................................................................................................3-10
Figure 3-12. Data Transmission Indicators.............................................................................................3-10
Figure 3-13. Configuration Page Navigator............................................................................................3-11
Figure 5-1. System Status Page (AUX Group Normal Mode)..................................................................5-1
Figure 5-2. Alerts & Annunciations..........................................................................................................5-2
Figure 5-3. WARNING Softkey Annunciation ........................................................................................5-3
Figure 5-4. CAUTION Softkey Annunciation..........................................................................................5-3
Figure 5-5. ADVISORY Softkey Annunciation .......................................................................................5-3
Figure 5-6. System Annunciations............................................................................................................5-4
Figure 5-7. GMA 1347 Data Paths .........................................................................................................5-12
Figure 5-8. GEA 71 Data Paths ..............................................................................................................5-19
Figure 5-9. GTX 33 Data Paths ..............................................................................................................5-20
Figure 5-10. GRS 77 Data Paths.............................................................................................................5-22

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Figure 5-11. GDC 74A Data Paths .........................................................................................................5-23
Figure 6-1. System Status Page (Configuration Mode) ............................................................................6-1
Figure 6-2. Configuration Module Installation .........................................................................................6-6
Figure 6-3. GEA Backshell Thermocouple...............................................................................................6-7
Figure 7-1. G1000 Normal Mode Check ..................................................................................................7-4
Figure 7-2. G1000 Reversionary Mode Check .........................................................................................7-4
Figure 7-3. Marker Beacon Symbology....................................................................................................7-7
Figure 7-4. GPS Signal Status.................................................................................................................7-11
Figure 7-5. G1000 Engine/Airframe Indicators......................................................................................7-16
LIST OF TABLES
TABLE PAGE
Table 1-1. Required Documents ...............................................................................................................1-3
Table 1-2. Reference Documents..............................................................................................................1-3
Table 4-1. Required Maintenance.............................................................................................................4-3
Table 4-2. 1000 Hour Inspection Procedure .............................................................................................4-5
Table 6-1. Thermocouple Kit (011-00981-00) .........................................................................................6-7

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1 INTRODUCTION
1.1 Content, Scope, Purpose
This document provides Instructions for Continued Airworthiness (ICA) for the Garmin G1000 Integrated
Cockpit avionics suite as installed in the Diamond Model DA 40 in accordance with the STC issued under
FAA STC SA01254WI. This document satisfies the requirements for continued airworthiness as defined
by 14 CFR Part 23.1529 and Appendix G. Information in this document is required to maintain the
continued airworthiness of the G1000 integrated cockpit system, as installed in the Diamond DA 40.
1.1.1 Applicability
This document applies to all Diamond Aircraft Industries, Inc., Model DA 40 aircraft equipped with the
G1000 cockpit installed in accordance with the STC issued under FAA STC SA01254 “original issue”
configuration. G1000 System Maintenance Manual – Diamond DA40 190-00545-00 applies to later
configurations.
1.2 Organization
The following outline briefly describes the organization of this manual:
Section 2: System Description
Provides a complete description of the type design change associated with installing the G1000
integrated cockpit system in the Diamond DA 40. An overview of the G1000 system interface is also
provided.
Section 3: G1000 Control & Operation
Presents basic control and operation information specifically tailored to maintenance practices. Basic
G1000 Configuration Mode operation is also described.
Section 4: G1000 Continued Airworthiness
Provides maintenance instructions for continued airworthiness of the G1000 system.
Section 5: Troubleshooting
Provides troubleshooting information to aid in diagnosing and resolving potential problems with the
G1000 system.
Section 6: G1000 Equipment Removal & Replacement
Gives instructions for the removal and replacement of G1000 equipment.
Section 7: G1000 Equipment Configuration & Testing
Gives instructions for loading software, configuring, and testing of G1000 equipment.
Section 8: System Return to Service Procedure
Specifies return-to-service procedures to be performed upon completion of maintenance of the G1000
system.
Appendix A: Installation Data
Gives a complete equipment/parts list and weight/balance data for the G1000 installation in the
Diamond DA 40.
Appendix B: G1000 Software/Configuration Procedure
Provides a complete software/configuration loading procedure in cases where the G1000 system as a
whole requires complete software/configuration update or reload. This is given in addition to
individual LRU configuration instructions presented in Section 7.

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1.3 Definitions/Abbreviations
ADI: Attitude Display Indicator
AHRS: Attitude Heading Reference System
AMM: Airplane Maintenance Manual
CDU: Control Display Unit
CFR: Code of Federal Regulations
EAU: Engine/Airframe Unit
EIS: Engine Instrumentation Systems
HIRF: High Intensity Radiated Fields
HSDB: High-Speed Data Bus (Ethernet)
IAU: Integrated Avionics Unit
ICS: Inter-Com System
LRU: Line Replaceable Unit
MFD: Multi-Function Flight Display
OAT: Outside Air Temperature
PFD: Primary Flight Display
STC: Supplemental Type Certificate
S/W: Software
TC: Type Certificate
TSO: Technical Standard Order
TVS: Transient Voltage Suppressor
VHF: Very High Frequency
1.3.1 Units of Measure
Unless otherwise stated, all units of measure are English units.

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1.4 Reference Publications
The following documents are required by this maintenance manual to perform maintenance:
Table 1-1. Required Documents
Document Garmin Part Number
G1000 Cockpit Reference Guide for DA40 190-00324-00
G1000/DA 40 Airplane Flight Manual Supplement 190-00303-02
Diamond DA 40 Wiring Diagram Diamond P/N:
DA4-9231-60-1
Diamond DA 40 Airplane Maintenance Manual Diamond P/N
6.02.01 (Rev. 4 or later)
The following documents provide additional information above and beyond the scope of this document:
Table 1-2. Reference Documents
Document Garmin Part Number
G1000/DA 40 Master Drawing List 005-C0004-00
G1000/DA 40 Required Equipment List 005-00149-28
G1000/DA 40 Install Drawing 005-00149-01
G1000/DA 40 Post Installation Checkout Procedure 190-00303-06
G1000 Configuration Manual 190-00303-04
Aircraft Fastener Assembly Torque 005-00249-00
Aircraft Contact and Terminal Crimping 005-00249-01
Heat Shrink Tubing Application 005-00249-02
Aircraft Soldering 005-00249-03
1.5 Distribution
This document is to be a permanent aircraft record and is distributed with a new G1000-equipped
Diamond DA 40. Revisions to this document will be made by Garmin and will be distributed by Garmin
per standard documentation revision procedures.

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2 SYSTEM DESCRIPTION
G1000 system installation can be accomplished only after the following Diamond aircraft modifications
have been installed:
•OAM 40-061 Autopilot (optional)
•OAM 40-68 Essential Bus
•OAM 40-073/b Slick Start System
•OAM 40-082/b IFR Lightning Protection
•OAM 40-146 Remote Avionics Provisions
•OAM 40-161/e G1000 Provisions Provisions with KAP 140 AFCS
Or OAM 40-196 G1000 Provisions without KAP 140 AFCS
•STC SA1850CH Hartzell Propeller
The G1000 integrated cockpit is installed in the DA 40 using the equipment listed in this section as well
as parts listed in Appendix A.
2.1 Equipment Descriptions
2.1.1 GDU 1040 MFD & PFD
Two Garmin GDU 1040 CDUs are installed in the Diamond instrument panel. One is configured as a
PFD and the other as a MFD (Configuration is determined by wiring harness). Both displays provide
control and display of nearly all functions of the G1000 integrated cockpit system. The displays are
located side-by-side with the GMA 1347 Audio Panel located in the middle (See Figure 2-1).
Electrical power to the PFD is from the ‘Essential’ power bus, whereas the MFD receives power from the
‘Main’ bus. Therefore, both displays power-up immediately when the aircraft master switch is turned on.
To provide proper electrical bonding, beryllium copper ‘finger’ strips are installed on the lower lip of the
display. This provides sufficient contact area to which the displays can be grounded to the airframe.
Both displays are installed in the Diamond panel using built-in ¼-turn fasteners. Each display uses an
existing connector per OAM 40-161. The ‘GDL 69’ and ‘WX500’ circuit breakers, if installed, are
pulled, banded with collars, and associated wires are disconnected and dressed with shrink tube.
Two CDU cooling fans are also installed behind the panel as shown in Figure 2-2.

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Figure 2-1. G1000 / DA 40 Panel Installation

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2.1.2 GMA 1347 Audio Panel
The Garmin GMA 1347 Audio Panel is a digital audio panel with integrated marker beacon receiver. The GMA
1347 provides control of all cockpit intercom/mic systems as well as NAV/COM/ILS audio. The unit also provides
display reversion mode control through a large red button. Power is received from the ‘Avionics’ bus. The unit
only powers up when the avionics master switch is turned on. The GMA 1347 interfaces with the existing marker
beacon antenna as well as existing mic and phone jacks.
2.1.3 GIA 63 Integrated Avionics Unit (2)
Two Garmin GIA 63 IAUs provide VHF COM, VHF NAV, GPS NAV and other various navigation functions.
GIAs provide communication interface to all other G1000 LRUs in the system. Both GIAs are located remotely
beneath the baggage compartment in a sheetmetal enclosure, as shown in Figure 2-6 and Figure 2-7. The #1 GIA is
powered through the ‘Essential’ power bus and immediately powers up when the aircraft master switch is turned on.
The #2 GIA receives power through the ‘Avionics’ bus and powers up when the avionics master switch is turned on.
Both GIA 63s interface to the following equipment:
•.....Existing KAP 140 Flight Control System (GIA 2)
•.....Existing VOR/LOC/Glideslope Antenna System
•.....Existing VHF COM 1 & 2 Antennas
•.....Existing GPS 1 & 2 Antennas
2.1.4 GEA 71 Engine/Airframe Unit
The Garmin GEA 71 Engine/Airframe Unit provides engine/airframe data to the G1000 system. Data received from
transducers/sensors is processed, then sent to GIA 63, and subsequently to the GDU 1040 MFD. In display
reversionary mode, engine instrumentation is displayed on the PFD as well. The GEA is located behind the
instrument panel and is mounted in a vertical orientation as depicted in Figure 2-2 and Figure 2-6. Power is received
from the ‘Essential’ power bus. The GEA interfaces to the following:
•.....Manifold Pressure Sensor (MAP)
•.....Oil Pressure Sensor
•.....Fuel Pressure Sensor
•.....Tachometer Sensor
•.....Oil Temperature Sensor
•.....Fuel Flow Sensor
•.....4 Cylinder Head Temperature (CHT) Sensors
•.....4 Exhaust Gas Temperature (EGT) Sensors
•.....Alternator Current Sensor
•.....Existing Fuel Probes
•.....Existing Pitot Heat System
•.....Existing Open Door Detection Switches
•.....Existing Starter Engage System
2.1.5 GTX 33 Mode S Transponder
The Garmin GTX 33 provides Mode A, C, and S altitude and position reporting information to the G1000
system. The unit is mounted in the remote avionics enclosure below the baggage compartment (See
Figure 2-6 and Figure 2-7). Power is received from the ‘Essential’ bus. The GTX 33 interfaces with the
existing transponder antenna.

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Figure 2-2. DA40 Panel (Rear View)

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2.1.6 GDC 74A Digital Air Data Computer
The Garmin GDC 74A provides digital air data computations to the G1000 system. The unit is mounted
horizontally behind the instrument panel and is fastened to a sheetmetal rack. Power is received from the
‘Essential’ bus. The GDC 74A connects to existing pitot/static ports as shown in Figure 2-2 and Figure
2-6.
2.1.7 OAT Probe
The Garmin GTP 59 OAT Probe provides the GDC 74A with air temperature data. The OAT probe is
mounted to the bottom starboard side of the DA 40 fuselage as shown in Figure 2-3.
Figure 2-3. GTP 59 OAT Probe

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2.1.8 GRS 77 Attitude & Heading Reference System
The Garmin GRS 77 AHRS provides attitude and heading information to the G1000 system. The unit is
mounted remotely in the baggage compartment, to the starboard side of the remote avionics enclosure
(see Figure 2-4 and Figure 2-6). Power is received from the ‘Essential’ bus. The GRS 77 interfaces with
and provides power to the GMU 44 Magnetometer. The GRS 77 supplies attitude and heading
information directly to the PFD, MFD, and to both GIAs.
Figure 2-4. GRS 77 Mount

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2.1.9 GMU 44 Magnetometer
The GMU 44 provides horizontal and vertical magnetic field information to the GRS 77 AHRS. This
allows heading to be calculated and provides assistance during AHRS alignment. The GMU 44 is
mounted beneath the starboard wing as shown in Figure 2-5 and Figure 2-6.
Figure 2-5. GMU 44 Installation

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2.2 Equipment Locations
GDC 74A
GDC 74A
Figure 2-6. G1000 in DA 40 Equipment Locations