Garmin MX20 Installation Manual - page 68
Troubleshooting
MX20 Installation Manual
61
Table 5-1. Troubleshooting Guide Cont’d
Problem Cause
Solution
1. Unit is not GTX330 capable.
1. Ensure that the model MX20 is
GTX330 capable.
2. Data port configured incorrectly. 2. Ensure that the data port
configuration is correct and the
GTX330 is set correctly.
3. Traffic function not enabled.
3. Ensure that the GTX330 function
is enabled.
4. GTX330 not powered up or not
functioning properly.
4. Ensure that the GTX330 has
power applied and is functional.
Unit shows XPDR data flag.
5. Wiring connections are incorrect. 5. Verify wiring and pin connections
Split Screen function does not
appear.
1. Split Screen function is not
enabled.
1. Enable Split Screen function in
INSTL mode function page.
Terrain annunciators do not
light during TAWS8000 self-
test.
1. ARINC 429 IN (J2-61 & J2-62)
wires are reversed.
1. Ensure the ARINC 429 wires are
connected to the proper pins.
Unit shows IDENT (Green)
1. This is not a problem. This is an
indication that the GDL 90 UAT
is in Identification mode. This
should be a temporary indication.
1. No action required.
No XM Satellite Radio Audio
1. Installed unit is a GDL 69, not
GDL 69A.
1. Only the GDL 69A has audio
outputs.
2. The GDL 69A, audio panel, or
both are not powered up.
2. Ensure GDL 69A and audio
panel have power applied.
3. Volume turned down or muted.
3. The GDL 69A mutes volume on
power up. Increase volume
through the MX20 user interface
or GDL 69/69A remote control
switches. (See GDL 69/69A
Installation Manual for details).
4. Headphone or speaker outputs on
audio panel are disabled.
4. Enable headphone or speaker
outputs on audio panel (refer to
audio panel documentation).
Some audio panels may require
software configuration changes.
5. Wiring connections are loose or
incorrect.
5. Verify wiring and pin
connections.