Garmin G5 Maintenance Manual page 26

7) If the LED indication is 'Alternating Red/Green', verify the Unit ID strapping on the G5 units.
Reference Section 5.3 wiring interconnects for the appropriate Unit ID strapping.
8) Verify the GPS Navigator configuration has not changed from that set in the initial installation.
Reference APPENDIX A .
9) If the problem persists, replace the GAD 29/29B with a known good unit.
5.1.8 Loss of Non Garmin Autopilot Heading and/or Course Datum (Installations
with GAD 29B Installed)
If the Non-Garmin autopilot loses the capability to couple and track Heading and/or Course Datum:
1) Complete troubleshooting as directed and applicable in Section 5.1.4 for loss of Heading Datum,
Section 5.1.6 for loss of Course Datum and Section 5.1.7 for loss of GPSS Datum. If these all
indicate there is no problem continue to the next step.
2) Inspect and verify the ARINC 429 Bus wiring between the GPS Navigator, GAD 29B and
autopilot computer.
3) Inspect and verify the Analog wiring between the GAD 29B and the autopilot computer.
4) Verify the G5 and GPS Navigator configurations has not changed from that set in the initial
installation. Reference APPENDIX A .
5) Verify the autopilot computer is functioning properly. Reference autopilot manufacturers
troubleshooting procedures.
6) If the problem persists, replace the GAD 29B with a known good unit.
5.1.9 GFC 500 Failure Messages
During operation of the GFC 500 AFCS, the G5 may annunciate a failure or fault that is specific to the
GFC 500 AFCS. Refer to the GFC 500 AFCS Maintenance Manual/ICA, 190-02291-01, for assistance
in troubleshooting the problem.
5.1.10 GPS Position Information Removed (Units with no NAV Interface)
If the GPS position information is removed from the G5 Attitude or HSI display (no GPS track or
Ground Speed).
1) On the G5 in configuration mode, select the RS-232 Configuration page, select Input Format and
verify there is a Green Check by MapMX. If there is a Red-X by MapMX, proceed to the next
step.
2) Check the RS 232 wiring connected between the G5 and the GPS Navigator using the instructions
in the General section above.
3) Verify the GPS Navigator configuration has not changed from the initial installation. Reference
APPENDIX A .
4) If the problem persists, replace the G5 with a known good unit.
Garmin G5 Electronic Flight Instrument Part 23 AML STC Maintenance Manual
Page 18 of 54
190-01112-11
Rev. 7