Garmin MX20 Installation Manual page 73

Problem
Unit shows XPDR data flag.
Split Screen function does not
appear.
Terrain annunciators do not
light during TAWS8000 self-
test.
Unit shows IDENT (Green)
No XM Satellite Radio Audio
MX20 Installation Manual
Table 5-1. Troubleshooting Guide Cont'd
Cause
1. Unit is not GTX330 capable.
2. Data port configured incorrectly.
3. Traffic function not enabled.
4. GTX330 not powered up or not
functioning properly.
5. Wiring connections are incorrect. 5. Verify wiring and pin connections
1. Split Screen function is not
enabled.
1. ARINC 429 IN (J2-61 & J2-62)
wires are reversed.
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. Installed unit is a GDL 69, not
GDL 69A.
2. The GDL 69A, audio panel, or
both are not powered up.
3. Volume turned down or muted.
4. Headphone or speaker outputs on
audio panel are disabled.
5. Wiring connections are loose or
incorrect.
560-1025-09 Rev E
Troubleshooting
Solution
1. Ensure that the model MX20 is
GTX330 capable.
2. Ensure that the data port
configuration is correct and the
GTX330 is set correctly.
3. Ensure that the GTX330 function
is enabled.
4. Ensure that the GTX330 has
power applied and is functional.
1. Enable Split Screen function in
INSTL mode function page.
1. Ensure the ARINC 429 wires are
connected to the proper pins.
1. No action required.
1. Only the GDL 69A has audio
outputs.
2. Ensure GDL 69A and audio
panel have power applied.
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. Enable headphone or speaker
outputs on audio panel (refer to
audio panel documentation).
Some audio panels may require
software configuration changes.
5. Verify wiring and pin
connections.
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