Troubleshooting Via The Cdu - Saab R5 Supreme Operation & Installation Manual

8.5.14 NAV: Anchor Alarm Distance Exceeded (ID 167)
This alarm is active when the anchor watch function is in operation and the range limit
has been exceed.
8.5.15 NAV: DGPS Integrity Alert (ID 169)
This alarm is active when any of the following conditions apply:
No DGPS Signal: A correction source for GPS other than None has been
selected in the GPS Configuration view and more than ten seconds have
passed since a new set of differential corrections were applied to the
navigation solution.
Station Unhealthy: Beacon has been selected as correction source for GPS
and the radio beacon station in use indicates an unhealthy status.
Station Unmonitored: Beacon has been selected as correction source for
GPS and the radio beacon station in use indicates an unmonitored status.
Poor Signal: Beacon has been selected as correction source for GPS and
word error rate of the received signal in use exceeds 10%.
8.6

Troubleshooting via the CDU

There is a lot of information and data accessible via the R5 SUPREME CDU that can be
useful for troubleshooting, and that can help finding a presumed problem. The following
items are just a few examples of what to look at.
8.6.1 Current Time
The time (UTC or LOC) in the upper right corner of the display is provided by the R4
Navigation Sensor. If the time is not correct, the R4 Navigation Sensor does not have a
position fix. This will also be indicated by the alarm ―Position Data Lost‖. This problem
is normally caused by a GPS-antenna failure or damaged antenna cables. This
problem may also be caused by interference from radio equipment on-board.
8.6.2 View RAW data
The View Raw Data view in the R5 SUPREME CDU is used to verify that data is
received on the ports and that the connected external sensors provide the correct
sentences.
The view shows the incoming data on the selected serial port. It is possible to pause
the data on the screen by pressing the ―Freeze‖ button. Received data during ―Freeze‖
will be discarded. The View Raw Data view can be a helpful tool when trouble shooting
the system to see what sensor input is actually received on each port. The view can be
accessed from Main Menu  Status  View Raw Data.
7000 118-301, A
R5
SUPREME - Navigation System
TROUBLESHOOTING
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