Garmin G1000 System Maintenance Manual page 129

MFD1 RS-232
Channel LRU
CHNL 1 GCU 477
G1000 / GFC 700 System Maintenance Manual - 300/B300 Series King Air
190-00716-01
Indicator Status
MFD1/GCU 477 data path is functioning correctly.
Green
MFD1/GCU 477 data path is not functioning correctly.
•
Verify GCU 477 is powered on.
o If GCU 477 will not power on, remove unit and
Red
•
Load MFD1 and GCU 477 configuration files.
•
Check the MFD1/GCU 477 interconnect wiring for faults.
•
Replace GCU 477.
Replace MFD if problem remains.
MFD1/GCU data path functionality is unknown. Reload MFD1
Amber
configuration file.
verify power and ground are present at the GCU
connector.
If power or ground is not present,
troubleshoot aircraft wiring for faults.
If power and ground are present, replace
GCU 477.
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Revision 1