Backup Communications Path Checks; Gdu 105X Troubleshooting - Garmin G1000 Nxi System Maintenance Manual

Backup Communications Path Checks

Overview
The G1000 system architecture is designed with redundant communication ports for several
LRUs so that critical information can continue to be displayed in the event of an equipment or
wiring failure. Of most importance is flight attitude, heading, and air data information. The GRS
77/7800 and GDC 7400 each have four separate ARINC 429 data lines which are all capable of
sending data to the displays. The GEA 71, GTX 33(D) or GTX 3000, and GMA 1347D each
have two redundant serial communication paths for the same purpose. See Figure 2-30 for a
basic G1000 block diagram depicting this architecture. Several other diagrams are shown later
in this section for illustrative purposes. When troubleshooting, refer to the G1000 Wiring
Diagram listed in Table 1-1.
Refer to Section 9.10 for procedures on checking the status of each configured
G1000 / GFC 700 backup data path.
Data Path Failures
Failure Message
FAILED PATH – A data path has
failed.

GDU 105X Troubleshooting

GDU 105X Symptoms
Symptom
Display is blank
Display resets
G1000 NXi System Maintenance Manual
King Air 300 Series
190-00716-N1
NOTE
Cause
A communications data path
status is not being received by the
G1000.
Recommended Action
•
Ensure that a cell phone or a device using cell phone technology is not turned
on (even in a monitoring state) in the cabin.
•
Cycle power.

If GDU recovers, observe display for yellow text containing error
information at the top of the screen. If message indicates software need
to be re-loaded, then re-load software. Otherwise, replace the GDU.
•
Use a bright light to verify LCD is active.

Adjust avionics dimmer control full clockwise.

Manually turn up backlight on the PFD and load configuration files to the
GDU.
•
Ensure slide lock is fully engaged with the locking tabs on the back of the unit.

If slide lock is not fully engaged, remove connector and verify the locking
tabs on the GDU are perpendicular to the connector. If necessary,
straighten them before reseating connector.
Solutions
•
Determine which data path has
failed: See Section 5.1.1.
•
Check wiring continuity for the failed
path.
•
Swap or replace the affected LRU.
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