Garmin GNC 420AW Installation Manual - page 106
Page 5-26
400W Series Installation Manual
Rev. E
190-00356-02
5.4.6
AHRS/IRU Interface Check
The GNS 400W Series unit can receive heading data from an external source. This check verifies that the
GNS 400W Series unit is receiving data from these units. Ensure that the GNS 400W Series unit is
turned on and in configuration mode. If the following steps do not perform correctly, check the electrical
connections and configuration setup.
1.
Go to the Main Inputs 1 page.
NOTE
If a Sandel EHSI or an ARINC 429 EFIS is also installed, ensure that it is turned off so
that it does not supply heading to the GNS 400W Series unit.
2.
Verify that the HDG field displays valid heading data.
3.
Remove power from the heading source and verify that the heading in the HDG field is dashed
out.