BendixKing KLN 900 - Pilots Guide - Manual (Page 199)

• NONVOLATILE RAM FAIL (The battery-backed
Random Access Memory has failed. Nonvolatile
memory will be cleared.)
If you encounter this error, turn the KLN 900 off
and then back on. If the problem continues to
occur after power has been cycled, return the
KLN 900 for service.
• RF SELF-TEST FAIL (This means the receiver is
not sensing a proper Radio Frequency signal
from the satellites/antenna.)
This is most often an installation related failure or
a bad antenna. Refer to Service Center for
installation troubleshooting.
• ASIC SELF-TEST FAIL (Internal error)
Return the KLN 900 for service.
• NO MILLISEC INTERRUPT (Internal error)
This is most often an installation related failure or
a bad antenna. Refer to Service Center for
installation troubleshooting.
• NO INITIALIZATION DATA (Internal error)
If you encounter this error, turn the KLN 900 off
and then back on. If the problem continues to
occur after power has been cycled, return the
KLN 900 for service.
• EEPROM MEMORY FAIL (The EEPROM has
failed self test.)
If you encounter this error, turn the KLN 900 off
and then back on. If the problem continues to
occur after power has been cycled, return the
KLN 900 for service.
• UART 2 LOOPBACK FAIL (Internal error)
This is most often an installation related failure.
Refer to Service Center for installation trou-
bleshooting.
• ONE MILLISEC UNDERFLOW (Internal error)
Return the KLN 900 for service.
• ONE MILLISEC OVERFLOW (Internal error)
Return the KLN 900 for service.
RECYCLE POWER TO USE
CORRECT DATA BASE DATA - This message
appears when the date entered on the Self-Test page is
before the data base effective date and the date entered
later on the SET 2 page is after the data base effective
date, or vice versa. Turn the KLN 900 off and back on
so that the correct data base data is utilized.
Rev 2
RAIM POSITION ERROR
CROSS CHECK POSITION - This message means that
the unit has detected a problem with one of the satellites
and the position cannot be assured to be within IFR
limits for the particular mode of flight. Cross check the
position of the aircraft with other means of navigation
frequently to verify that the position is still accurate. If
this message becomes a persistent problem, return the
KLN 900 for service.
Receiver Automonous Integrity Monitoring (RAIM) is a
method of calculating integrity in the GPS position. The
KLN 900 calculates the position multiple times using dif-
ferent sets of satellites and compares the answers. If
they have excessive difference, the message appears.
RAIM NOT AVAILABLE
CROSS CHECK POSITION - This message appears
when there are not enough received GPS satellite
signals to compute integrity (RAIM). Cross check the
position of the aircraft with other means of navigation
frequently to verify that the position is still accurate. If
this message becomes a persistent problem, it may be
necessary to refer to your Service Center for installation
troubleshooting.
This message may be caused by any of the following:
1. The satellites are blocked from view by obstructions.
2. The satellites are too low on the horizon for use or
there is insufficient geometry to support RAIM.
3. There is signal loss in the antenna, the coax, or
receiver module.
The aircraft should be in an open area with good visibility.
The KLN 900 will usually have 6-8 satellites shown on the
STA 1 page, and the majority of their SNR’s (Signal to
Noise Ratios) will be in the 40’s. SNR’s of 30 and below
are unusable, 30-35 are marginal, and 35-48 are consid-
ered good.
RCVR HARDWARE ERROR:_____- (Receiver
Hardware Error) This message appears when the
KLN 900 fails a specific internal test for the GPS
receiver. The blank will contain a numerical value which
may provide assistance to maintenance personnel.
One or more of the following descriptions will appear
after the “RCVR HARDWARE ERROR: ____” message
line. Please follow the instructions for the message(s)
which you are observing.
• EPROM FAIL (EPROM Failure)
Return the KLN 900 for service.
• RAM FAIL (Random Access Memory Failure)
Return the KLN 900 for service.
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