Garmin G1000 Maintenance Manual page 47

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GDU RS-232 / ARINC 429 CONFIG Page
PFD1 RS-232
Channel LRU
GCU 476
(certain
CHNL 1
airframes
only)
G1000 System Maintenance Manual
190-00907-00
Indicator
PFD1/GCU 476 data path is functioning correctly.
PFD1/GCU 476 data path is not functioning correctly.
•
Check PFD Alert Window for PFD or GCU
configuration or software error messages. Correct any
errors before proceeding.
•
Verify 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 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, check the PFD
and GCU connector for damaged or pushback
pins.
•
Swap PFD and MFD to confirm if the problem is in the
PFD.
•
Replace original PFD if box turns green after
swapping displays.
•
Replace the GCU.
PFD1/GCU 476 data path functionality is unknown. Reload
PFD1 configuration file.
Status
Page 5-11
Rev. B