Garmin G900X Installation And Maintenance Manual page 493

C.2.21.6 GDU Failure Test
Step
MFD Display Failure Conditions:
1. Remove power from MFD.
2. Check for desired results.
3. Restore power to MFD.
PFD Display Failure Conditions:
1. Remove power from PFD.
2. Check for desired results.
3. Replace power to PFD.
G900X/G950 Installation and Maintenance Manual – PICP & Warranty Registration
190-00719-00
Desired Result
The following shall occur when power is removed
from the MFD:
PFD switches to reversion mode
Attitude and Heading remain valid from AHRS
Airspeed, Altitude, Vertical Speed, and OAT
remain valid from Air Data Computer
Valid Engine Instrumentation appears on PFD
XPDR field remains valid on PFD
COM2/NAV2 fields flag invalid
The following shall occur when power is removed
from the PFD:
MFD switches to reversion mode
Attitude and Heading remain valid from AHRS
Airspeed, Altitude, Vertical Speed, and OAT
remain valid from Air Data Computer
MFD retains engine instrumentation
Valid XPDR field appears on MFD
COM1/NAV 1 fields flag invalid
"XTALK ERROR – A flight display crosstalk error
has occurred" alert message on MFD
Page C-49
Revision D