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Cirrus Perspective™ Line Maintenance Manual
Page 5-19
190-00920-00
Rev.
E
MFD
RS
‐
232
Channel
LRU
Indicator
Status
CHNL
1
GCU
478
MFD/GCU
478
data
path
is
functioning
correctly.
MFD/GCU
478
data
path
is
not
functioning
correctly.
•
Check
PFD
Alert
Window
for
MFD
or
GCU
configuration
or
software
error
messages.
Correct
any
errors
before
proceeding.
•
Make
sure
the
GCU
is
powered
on
by
pressing
the
“ANN
TEST”
softkey
on
the
MFD
AUX
‐
SYSTEM
STATUS
page
to
see
if
the
key
indicators
turn
on.
•
If
GCU
will
not
power
on,
remove
unit
and
make
sure
power
and
ground
are
present
at
the
GMC
connector.
−
If
power
or
ground
is
not
present,
troubleshoot
aircraft
wiring
for
faults.
−
If
power
and
ground
are
present,
check
the
MFD
and
GCU
connectors
for
damaged
or
pushback
pins.
•
Swap
PFD
and
MFD
to
see
if
the
problem
is
in
the
original
MFD.
−
Replace
original
MFD
if
box
turns
green
after
swapping
displays.
•
Replace
the
GCU
478.
MFD/GCU
478
data
path
functionality
is
unknown.
Reload
MFD
configuration
file.