Garmin G3X Touch, Maintenance Manual

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Maintenance Manual 190-02472-02
G3X Touch EFIS Part 23 AML STC Revision 2
Page 37
Symptom Possible Cause Recommended Action
Verify that the Electrical Load Analysis and Battery
Capacity Analysis have been performed with
satisfactory results per the
G3X Touch EFIS Part 23
AML STC Installation Manual (190-02472-01) Sections
3.6.1 and 3.6.2.
Install a GAD 27
If troubleshooting does not reveal any anomalies in the
aircraft’s battery or electrical system, a GAD 27 may be
optionally installed per the
G3X Touch EFIS Part 23
AML STC Installation Manual (190-02472-01) to
address the issue
5.4 GSU 25D ADAHRS and GMU 11 Magnetometer Troubleshooting
5.4.1 Air Data Troubleshooting
Under normal operating conditions, the ADAHRS provides the following air data information:

Total Air Temperature is measured

Outside Air Temperature (OAT) – A valid OAT will display a number

Indicated Airspeed (IAS)

True Airspeed (TAS) – A valid OAT value is required to calculate TAS

Barometric Altitude

Density Altitude

Pressure Altitude

Static Pressure

Differential Pressure
NOTE
TAS information can only be displayed at speeds greater than 20 Knots (TAS is invalid
when the aircraft is sitting still, or if no OAT probe is connected).
Reference Table 5-6 for troubleshooting guidance.
Table 5-6 – ADAHRS and Magnetometer Troubleshooting
Symptom or Failure
Message
Possible Cause Recommended Action
Heading failure (Red X’d
intermittently or steady)
Improper installation of the
GMU 11 and/or GSU 25D Verify GMU 11 and GSU 25D mounting
locations are in accordance with the
G3X
Touch EFIS Part 23 AML STC Installation
Manual
(190-02472-01)
Excessive magnetic
interference
(determine if any
new equipment has been
installed on the aircraft near the
magnetometer)
Perform the magnetic interference test in
Section 8.12.1