Garmin 400W Series Instructions Manual page 16

Problem
RS-232 device is not
communicating with
the
400W/420W/430W.
Fan Fail Annunciation.  Wiring connections are incorrect.
400W Series
Instructions for Continued Airworthiness Bell 407
Possible Cause
 400W Series unit RS-232 port not
configured correctly.
 Improper setup on the remote
device.
 Device not compatible, or improper
connection.
 Multiple TX lines connected
together.
 Wiring connections are incorrect.
 Fan has failed.
Solution

Check RS-232 port setting for port that
device is connected to.

Verify the configuration of the other
device.

Verify 400W Series unit RX is connected
to remote device TX and 400W Series
unit TX is connected to remote device
Rx.

Verify that there is only one TX source
per RX port.

Check wiring.

Check wiring.

Replace fan.
190-01226-14 Rev. 3
Page 16 of 26