__________________________________________________________________
Page 8-4
Cirrus Perspective™ Line Maintenance Manual
Rev. E
190-00920-00
•
NAV1
CDI
deviation
bar
is
removed.
•
XTALK
ERROR
alert
is
given.
8.4
GCU
478
TEST
PROCEDURE
Perform
a
basic
operational
check
on
the
GCU
478.
Ensure
the
following:
1.
Proper
response
to
button
presses,
joystick
positions,
and
knob
turns.
2.
Proper
keypad
back
light
dimming
capability.
3.
No
stuck
keys.
4.
Proper
response
to
joystick
movements
and
positions.
5.
Ensure
the
photocell
is
well
lit.
8.5
BACKUP
PATH
TESTS
Pull
the
PFD
and
MFD
circuit
breakers
and
remove
power
from
both
displays
before
performing
these
tests.
Reboot
the
PFD
and
MFD
by
pressing
and
holding
the
12
th
softkey
on
the
MFD
until
the
words
INITIALIZING
SYSTEM
appear.
1.
Go
to
the
GDU
Page
Group
on
the
PFD
in
configuration
mode.
2.
Activate
the
cursor
3.
Select
PFD1
in
the
SELECT
UNIT
field
and
press
ENT.
4.
View
the
GRS
77
#1
and
GDC
74
#1
DATA
indicators
in
the
ARINC
429
window
and
make
sure
both
indicators
are
GREEN
which
indicates
the
channels
are
receiving
data
as
shown
in
Figure
8
‐
1.
5.
Activate
the
cursor.
6.
Select
MFD1
in
the
SELECT
UNIT
field,
and
press
the
ENT
key.
7.
View
the
GRS
77
#2
and
GDC
74
#2
DATA
indicators
in
the
ARINC
429
window.
Make
sure
both
indicators
are
GREEN
which
indicates
the
channels
are
receiving
data
as
shown
in
Figure
8
‐
1.
