Grs 77 Related Alerts - Garmin CIRRUS PERSPECTIVE SR20 Line Maintenance Manual

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5.9.2 GRS 77 Related Alerts
Message
AHRS1 TAS – AHRS1 not
receiving airspeed.
AHRS2 TAS – AHRS2 not
receiving airspeed.
AHRS1 GPS – AHRS1 using
backup GPS source.
AHRS1 GPS – AHRS1 not
receiving backup GPS
information.
AHRS1 GPS – AHRS operating
exclusively in no‐GPS mode.
AHRS1 GPS – AHRS1 not
receiving any GPS
information.
AHRS2 GPS – AHRS2 using
backup GPS source.
AHRS2 GPS – AHRS2 not
receiving backup GPS
information.
AHRS2 GPS – AHRS2
operating exclusively in no‐
GPS mode.
AHRS2 GPS – AHRS2 not
receiving any GPS
information.
AHRS1 SRVC – AHRS1
magnetic field model needs
update.
AHRS2 SRVC – AHRS2
magnetic field model needs
update.
Page 5-72
Rev. E
Cause
The GRS 77 #1 is not
receiving airspeed
information from the GDC
74A #1.
The GRS 77 #2 is not
receiving airspeed
information from the GDC
74A #2.
GRS 77 #1 is using a
backup GPS source.
GRS 77 #1 is not receiving
backup GPS information
from either GIA 63W.
The GRS 77 is operating in
the absence of GPS.
GRS 77 #1 is not receiving
GPS data from either
GIA 63W.
GRS 77 #2 is using a
backup GPS source.
GRS 77 #2 is not receiving
backup GPS information
from either GIA 63W.
The GRS 77 #2 is
operating in the absence
of GPS.
GRS 77 #2 is not receiving
GPS data from either
GIA 63W.
AHRS #1 magnetic field
model has expired.
AHRS #2 magnetic field
model has expired.
Solutions
•
Check GRS #1/GDC 74A #1
interconnect.
•
Replace the GDC 74A #1
•
If problem does not clear, replace
the GRS 77 #1
•
Check GRS #2/GDC 74A #2
interconnect
•
Replace the GDC 74A #2
•
If problem does not clear, replace
the GRS 77 #2
•
Make sure a cell phone or a device
using cell phone technology is not
turned on (even in a monitoring
state) in the cabin.
•
Check GPS status for GIA 1 and 2 on
MFD ‐ AUX GPS STATUS page. If one
or both GPS receivers cannot
acquire a position lock.
Troubleshoot GPS problems using
Sections 5.1.2 and 5.6.2.
•
Replace the GRS 77.
•
Make sure a cell phone or a device
using cell phone technology is not
turned on (even in a monitoring
state) in the cabin.
•
Check GPS status for GIA 1 and 2 on
MFD ‐ AUX GPS STATUS page. If one
or both GPS receivers cannot
acquire a position lock.
Troubleshoot GPS problems using
Sections 5.1.2 and 5.6.2.
•
Replace the GRS 77.
•
Reference Garmin SB 0533 for
update instructions.
Cirrus Perspective™ Line Maintenance Manual
190-00920-00