System Maintenance Manual

Page 7-6 G1000/GFC700 System Maintenance Manual – C90A/C90GT/C90GTi King Air
Revision F 190-00682-01
7.2.1.6 Marker Beacon Test
Figure 7-2. Marker Beacon Symbology
1. Using a ramp tester, simulate the outer marker, middle marker and inner marker signals by following
the test equipment manufacturer’s instructions. Verify that each marker audio signal is present over
the pilot and co-pilot headphones and speaker.
2. Verify that the outer, middle, and inner annunciations appear on PFD 1 and PFD 2 when the
corresponding signal is applied. Marker beacon annunciations appear at the upper left corner of the
altitude indicator on the PFD (Figure 7-2). Operate the MKR MUTE key on the #1 and #2 GMA
1347D and ensure that the audio signal is muted.
3. If no other service is to be performed, continue to the return-to-service checks in Section 8.