G1000 / GFC 700 System Maintenance Manual - 300/B300 Series King Air
Page 5-67
190-00716-01
Revision 1
5.15 GRS 77/GMU 44 Troubleshooting
5.15.1
AHRS Common Problems
Symptom Recommended
Action
AHRS does not complete
initialization
•
Ensure that a cell phone or a device using cell phone technology is not
turned on (even in a monitoring state) in the cabin.
•
Ensure GPS has acquired at least four satellites, has a 3D navigation
solution, and a DOP of less than 5.0. This is particularly important if
this issue appears during ground operation only.
•
Calibrate the GRS 77.
•
Check GRS 77 configuration module wiring for damage.
•
Check GRS 77 connector for bent pins.
9
If no damage can be found, replace GRS 77 configuration module.
9
If problem persists, replace the GRS 77.
Attitude appears unstable
•
Ensure that a cell phone or a device using cell phone technology is not
turned on (even in a monitoring state) in the cabin.
•
Ensure the four GRS 77 mounting screws are tight. Finger tight is not
sufficient, a screwdriver must be used to verify.
•
Ensure mounting rack and airframe shelf are secure and all hardware
and brackets are present (CAUTION - do not loosen the mounting rack
hardware to the airframe shelf or the aircraft will need to be re-leveled
and the PITCH/ROLL OFFSET procedure performed).
•
Ensure GRS 77 connector is securely fastened and proper strain relief
is provided.
•
Remove GRS 77 connector and verify there are no bent pins.
•
Replace the GRS 77.
•
Contact Garmin for further troubleshooting if required.
Summary of Contents for Cessna Caravan G1000
Page 2: ...This page intentionally left blank...
Page 89: ......
