Garmin G1000 Troubleshooting

1. General
A. This section gives the troubleshooting procedures for the Garmin G1000 GDC air data computer. For a general overview
of the Garmin GDC 72/74A ADC refer to Garmin G1000 Air Data Computer System - Description and Operation .
2. Garmin GDC ADC Troubleshooting
A. Tools and Equipment
NOTE: For the supplier publication part number and manufacturer data, refer to the Introduction - Supplier
Publication List.
(1) Tools and Equipment
• Multimeter.
(2) Special Consumables
• None.
(3) Reference Material
• Pitot/Static System - Adjustment/Test
• Garmin G1000 Air Data Computer System - Removal/Installation
• GTP 59 Outside Air temperature (OAT) Probe - Maintenance Practices
• Garmin G1000 Integrated Avionics System - Adjustment/Test
• Model 208 Wiring Diagram Manual.
B. Do the Airspeed, Altitude and Vertical Speed Fail Troubleshooting.
NOTE: A "X" (red) is shown over the primary flight display area for a failed indication.
(1) Connect external electrical power to the airplane.
(2) Make sure that the circuit breakers given in Table 101 are engaged.
Table 101. Circuit Breakers
Component
GDC 72/74A ADC 1
GDC 72/74A ADC 2
GDC 72/74A ADC Configuration
Module 1
GDC 72/74A ADC Configuration
Module 2
(3) Refer to Chapter 34, Garmin G1000 Integrated Avionics System - Adjustment/Test G1000 Architecture Verification
Check and make sure that:
(a) The correct software and configuration has been installed.
(b) All related systems are serviceable.
(c) The LRU serial number or a version number is not dashed.
(4) Make sure the COM1, COM2, GIA1 and GIA2 have check marks (green) next to their nomenclature on the list.
(a) This indicates the LRU is serviceable.
(5) Make sure that on the System Status List the GDC1 and/or GDC2 do not show a red X.
(6) Check the primary flight display crew alert system (CAS) window for messages to aid in troubleshooting the anomaly.
(7) If the Garmin GIA shows an amber X on the Avionics Status page, make sure that the electrical power and ground
connections to the GIA is serviceable. Refer to the Model 208 Wiring Diagram Manual, Chapter 20, Wiring -
Maintenance Practices.
(8) If the Architecture Verification check shows a serial number or a version number dashed on the Avionics Status page,
carefully examine the electrical wiring and components as follows:
NOTE:
Copyright © Textron Aviation Inc.
Retain printed data for historical reference only. For future maintenance, use only current data.
GARMIN G1000 AIR DATA COMPUTER SYSTEM - TROUBLESHOOTING
Serial number is not reported for the following equipment: COM1, COM2, GS1, GS2, GTX1, GTX
2 (OPT), NAV1, NAV2, AND WX500.
Circuit Breaker Name
ADC 1
ADC 2
ADC 1
ADC 2
Model 208/208B Maintenance Manual (Rev 33)
34-11-10-1 (Rev 33)
Circuit Breaker Location
Avionics Circuit Breaker Panel
Avionics Circuit Breaker Panel
Avionics Circuit Breaker Panel
Avionics Circuit Breaker Panel
Print Date: Thu May 18 07:30:03 CDT 2023
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