190-02207-A2
GPS 175/GNX 375/GNC 355 Part 23 AML STC Maintenance Manual
Rev. 3
Page 8-2
8.1 Overview
This section contains instructions for configuring the GPS 175/GNX 375/GNC 355, as well as checks to
ensure the system is properly installed and functioning correctly. The steps that are not applicable to a
particular installation may be skipped.
8.2 System Checkout
Original GPS 175/GNX 375/GNC 355 is Re-installed
If the removed GPS 175/GNX 375/GNC 355 is installed in its original position, no software loading or
configuration setting changes are required. This does not include units that were returned for repair, as
their software and configuration files are deleted during the repair testing process.
If the original GPS 175/GNX 375/GNC 355 is re-installed, configuration and software loading are not
required. Refer to Section 6 of
GPS 175 Part 23 AML STC Installation Manual
(P/N 190-02207-A1),
GNX 375 Part 23 AML STC Installation Manual
(P/N 190-02207-A4), or
GNC 355 Part 23 AML STC
Installation Manual
(P/N 190-02207-A5) (as applicable) for installation checkout procedures.
New, Repaired, or Exchanged GPS 175/GNX 375/GNC 355 is Installed
If a new, repaired, or exchanged GPS 175/GNX 375/GNC 355 is installed, the AML approved software
and the configuration files from the Configuration Log in the aircraft permanent records must be loaded to
the unit. After this is accomplished, refer to Section 6 of
GPS 175 Part 23 AML STC Installation Manual
(P/N 190-02207-A1),
GNX 375 Part 23 AML STC Installation Manual
(P/N 190-02207-A4), or
GNC 355
Part 23 AML STC Installation Manual
(P/N 190-02207-A5) (as applicable) for installation checkout
procedures.
8.3 GPS 175/GNX 375/GNC 355 Configuration
Retrieve the Configuration Log from the aircraft permanent records. For the maintenance activities that
repaired or replaced the previous GPS 175/GNX 375/GNC 355, configure the unit as defined by the data
contained in the Configuration Log.
NOTE
Ensure the Configuration Log remains with the aircraft permanent records upon
completion of any maintenance activities.
8.4 Regulatory Test (GNX 375)
The following regulatory tests are required to be performed per the 14 CFR sections referenced below. For
the purpose of these tests, ensure the GNX 375 transponder is in Ground Test mode to simulate an airborne
state. The Altitude Reporting Equipment Test is required to be performed for each altitude source
interfaced to the transponder, including the GAE 12. These tests require the use of a Mode S transponder
ramp tester, such as an Aeroflex IFR-6000 or TIC TR-220. For instructions on the operation of the ramp
test equipment, refer to the manufacturer’s documentation.
1. Altitude Reporting Equipment Tests in accordance with 14 CFR Part 91.411 and Part 43
Appendix E.
2. ATC Transponder Tests and Inspections in accordance with 14 CFR Part 91.413 and Part 43
Appendix F.
