Garmin GDL 90, Руководство по установке

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Troubleshooting
560-1049-02 Rev. B GDL 90 Installation Manual
5-4
"MSG 069: ARINC 743 position source timeout."
Comment: The GDL 90 is not receiving the expected ARINC labels
from the ARINC GPS sensor. Check the equipment installation and
wiring, and the APM configuration. Contact the factory if the problem
cannot be resolved.
"MSG 070: External 1PPS invalid."
Comment:
The GDL 90 is not sensing a valid 1PPS signal from the
ARINC 743 GPS sensor. Check the equipment installation and wiring,
and the APM configuration. Verify that the GPS sensor has a GPS
position solution. Contact the factory if the problem cannot be resolved.
5.3 How to View the GDL 90 Internal GPS Status on an MX20 (If equipped)
Note: similar procedures apply if the aircraft has a GMX 200.
With the aircraft positioned outside and powered-up in view of the sky, start up the GDL 90 and the
MX20. After startup, the MX20 ADSB flag should be shown. This indicates that the GDL 90 does not
yet have a position fix.
Look at the MX20 SYS - INFO page (press the FN key until SYS appears, press it, and then press the
INFO button). In the lower right corner is a box labeled "Datalink Status". You should see that the Count
value next to the label "HB" is incrementing, and that it says "Active" next to it. HB stands for Heartbeat,
this is a status message the GDL 90 sends to the MX20 every second.
If there are any UAT equipped aircraft in the area, or if you are in range of a UAT ground station, the
Status for the ADS-B and FIS items will show activity as well.
Also on the SYS - INFO page, in the lower left corner is a box labeled "Port Status", you should see that
Port 4 is labeled as "UAT", and that the "Data?" column says Yes, and the "Valid?" column also says
Yes.
Below the Port 4 status, on the line that starts with "GDL90", you should see values next to the "NIC"
and "NACp" labels. These values give the status of the GDL 90 internal GPS engine. While the GDL 90
is finding a GPS fix, the two values will be 0 and 0. If GPS satellites are visible, within about 2 minutes
of power-up you should see the NACp value start to increase, followed shortly by the NIC value. The
higher the number, the better the integrity and accuracy of the GPS fix. The values range from 0 to 11,
and anything higher than 5 is acceptable. The MX20 ADSB flag should turn off, and the green LED on
the front of the GDL 90 will be solid ON.
If any of these checks are not successful, double-check that the MX20 and GDL 90 are configured
correctly, and that the installed wiring agrees with the interconnection diagrams. If the aircraft is
equipped with an MX20, and a digital camera is available, it would be very helpful to take a close-up
picture of the entire MX20 SYS-INFO page and email it to Garmin Technical Support (see Section 5.4
for instructions).
5.4 Contacting the Factory for Assistance
If the GDL 90 unit fails to operate despite troubleshooting efforts, contact Garmin AT Technical Support
for assistance.
Garmin AT, Inc.
2345 Turner Rd. SE
Salem, Oregon 97302
USA