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190-02207-A2
GPS 175/GNX 375/GNC 355 Part 23 AML STC Maintenance Manual
Rev. 3
Page 3-9
3.4.4.4 Discrete Outputs
The
Discrete Outputs
page displays the state of each of the discrete outputs on the GPS 175/GNX 375/
GNC 355. This page also allows for the discrete outputs to be toggled between the Active and Inactive
states. This is useful for ensuring that these signals output are properly connected to annunciator lights or
other LRUs and that they are receiving the signal.
3.4.4.5 HSDB Ethernet
The
HSDB Ethernet
page displays the status of the HSDB Ethernet port and the status of any LRUs that
are interfaced to the GPS 175/GNX 375/GNC 355 via HSDB. The Ethernet port will display either
Not
Configured
,
Receiving
, or
Not Receiving
. For each LRU (GDU/GDL 88/GTX 345), the page will display
either
Online
or
Offline
.
3.4.4.6 XPDR (GNX 375 Only)
The GNX 375 monitors internal systems to verify functionality. Errors are displayed as Pilot Alerts,
Failures, Faults, and Warnings. Failures are the most severe, followed by Faults, Warnings, and then pilot
alerts. The
XPDR
page allows the user to view the status of all failure conditions, active faults, active
warnings, and associated pilot alerts. For troubleshooting of these errors, refer to the XPDR Alert
Troubleshooting flowcharts beginning with Figure 5-6.
3.4.4.7 Main Indicator (Analog)
The
Main Indicator (Analog)
page displays the status of the analog deviation and flag outputs to the CDI.
These can be changed and the output viewed on the CDI for the purpose of performing ground checks on
the analog CDI interface.
3.4.4.8 Composite Indicator
The
Composite Indicator
page displays the status of the composite deviation and vertical/lateral flag
outputs to the CDI. These can be changed and the output viewed on the CDI for the purpose of performing
ground checks on the composite CDI interface.
3.4.4.9 Analog Inputs
The
Analog Inputs
page displays the lighting bus voltages for Bus Setting and Input Voltage.
3.4.4.10 Gillham Encoder (GNX 375 Only)
The
Gillham Diagnostics
page displays the status and discrete pin settings for the Gillham altitude input.
3.4.4.11 Power Stats
The
Power Stats
page displays the number of times the GPS 175/GNX 375/GNC 355 has powered up and
the total elapsed operating hours for the GPS 175/GNX 375/GNC 355.