Additional Troubleshooting - Garmin GI 275 Installation Manual

7.2 Additional Troubleshooting

If necessary, perform the following troubleshooting steps:
1. The GI 275 air/ground logic must be on-ground when making any configuration changes or
attempting to load software. If the system is in-air while attempting system configuration changes
or software loads, system failures will occur. For example, an air data test set can trigger an
unexpected in-air state. Ensure:
a. Airspeed is less than 30kts – Pitot input can cause inadvertent airspeed inputs causing
unintended inputs.
b. GPS ground speed must be less than 30kts. – Using a GPS repeater can create issues with the
GPS system switching between satellite acquisition from an outside signal and the repeater
signal causing false GPS ground speed readings.
c. For units with EIS, the RPM readings must be 0 RPM while entering Configuration mode.
2. Ensure every GI 275 is in Configuration mode prior to making any configuration change.
3. Ensure every unit in the system has matching software.
4. For AHRS and autopilot configuration issues, ensure the above steps are completed and attempt to
reset the expansion board configuration using the following procedure in Configuration mode:
a. From the Interfaces page, configure the AHRS and ADC sensors as None on all units.
b. From the Interfaces page, configure the Autopilot configuration as None on all units.
c. If an ADI is configured, from the Unit Configuration page, change the Instrument Type to
MFD and then back to ADI.
d. If an HSI is configured, from the Unit Configuration page, change the Instrument Type to
MFD and then back to HSI (re-select the Standby selection if it appropriate).
e. From the Interfaces page, reconfigure AHRS and ADC sensors on all units as appropriate.
f. From the Interfaces page, reconfigure the Autopilot on all units as appropriate.
g. Reconfigure the Discrete In "Display Backup" discrete on the unit configured as the
standby, if appropriate.
h. Cycle system power by removing power from the GI 275 units.
5. GFC 500 servo faults can be cleared by completing the following procedure:
a. On the GI 275 in Configuration mode, navigate to the GFC 500 page (Config →
Diagnostics → GFC 500).
b. From this page, the servo fault can be cleared. Once the faults are cleared, the GFC 500
configuration must be synchronized.
c. Navigate to the GFC 500 Settings page (Config → Interfaces → Autopilot → Settings).
d. From this page, scroll to the bottom and touch Copy Config From GI 275 to GFC 500.
e. Cycle power to the GI 275(s) and the GFC 500.
6. For GFC 500 configuration issues, ensure the following steps have been completed:
a. The GI 275 Internal AHRS/ADC is configured (Config → Interfaces → ADC or AHRS).
b. GFC 500 interface is properly configured (Config → Interfaces → Autopilot).
c. The Copy Config From GI 275 to GFC 500 has been performed (Config → Interfaces →
Autopilot → Settings).
d. Ensure the Manifest has been sync'd.
e. Minimum approved SW on the GMC 507 and the GSAs has be installed.
f. Autopilot Calibration has been performed (without the above steps completed, this
calibration will not be available).
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Rev. 11
GI 275 Part 23 AML STC Installation Manual
Page 7-18