Page D-12
G900X/G950 Installation and Maintenance Manual – Troubleshooting
Revision D
190-00719-00
MFD RS-232
Channel LRU Indicator
Status
MFD/GCU 476 data path is functioning correctly.
MFD/GCU 476 data path is not functioning correctly.
•
Check PFD Alert Window for MFD 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 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 confirm if the problem is in the
original MFD.
−
Replace original MFD if box turns green after
swapping displays.
•
Replace the GCU 478.
-CHNL 1
GCU 476
(if equipped)
MFD/GCU 476 data path functionality is unknown. Reload
MFD configuration file.