190-01007-C1
GTN Xi Part 23 AML STC Maintenance Manual
Rev. 1
Page 7-14
7.3.3.2 Sandel SN3308 Interface Check
If a Sandel EHSI has been connected to the GTN Xi, the interface should be verified as described in one of
the following sections, as appropriate for the installation.
7.3.3.2.1 Single GTN Xi/Single SN3308
1. Cycle power to the GTN Xi and acknowledge the prompts until on the
Instrument Panel Self-Test
page (refer to Section 6.1.1).
2. Ensure that the SN3308 receives valid heading.
NOTE
The Vertical Deviation Indication will not be displayed unless the SN3308 is receiving
valid heading.
3. While the GTN Xi is displaying the
Instrument Panel Self-Test
page, verify that the SN3308
displays the following data from the GPS source:
Course Deviation: Half-scale left deviation, TO indication, flag pulled
Vertical Deviation: Half-scale up deviation, flag pulled
Active Waypoint: GARMN
4. On the GTN Xi, verify that an OBS value displays and is not dashed out.
5. Acknowledge the self-test on the GTN Xi by touching the
Continue
key.
6. Select
VLOC
on the GTN Xi and verify that the SN3308 displays NAV 1 or NAV 2 (depending on
the GTN Xi navigation source configuration).
7. Using a VOR test set, verify that the CDI deviation on the SN3308 displays correctly.
7.3.3.2.2 Dual GTN Xi Units/Single SN3308
1. Remove power from GTN Xi #2 by opening up the circuit breaker.
2. Cycle power to GTN Xi #1 and acknowledge the prompts until on the
Instrument Panel Self-Test
page (refer to Section 6.1.1).
3. Select GPS1 as the navigation source by pressing the
NAV
key on the SN3308. Verify that “GPS1”
displays on the SN3308.
4. Ensure that the SN3308 receives valid heading. The Vertical Deviation Indication will not display
unless the SN3308 receives valid heading.
5. While GTN Xi #1 displays the
Instrument Panel Self-Test
page, verify that the SN3308 displays
the following data from GPS1:
Course Deviation: Half-scale left deviation, TO indication, flag pulled
Vertical Deviation: Half-scale up deviation, flag pulled
Active Waypoint: GARMN
6. On GTN Xi #1, verify that an OBS value displays and is not dashed out.
7. Acknowledge the self-test on GTN Xi #1 by touching the
Continue
key.
8. Select
VLOC
on GTN Xi #1 and verify that the SN3308 displays “NAV 1” or “NAV 2” depending
on which navigation source the GTN Xi is.
9. Using a VOR test set, verify that the CDI deviation on the SN3308 displays correctly.
