Instruction Manual

Instructions for Continued Airworthiness 190-00792-12 Rev 1
for the Garmin G500H Installation in Eurocopter AS350 Page 42 of 80
a) GMU 44, Magnetometer Removal and Installation
i Removal
1. Access the GMU 44 magnetometer (reference Section 6-00-00 Dimensions and
Access).
2. Unscrew the three screws that hold the GMU 44 to its mounting rack.
3. Carefully lift the GMU 44 from the rack.
4. Disconnect the wiring harness.
ii Installation
1. Visually inspect the connectors to ensure there are no bent or damaged pins.
Repair any damage.
2. Connect the wiring harness to the GMU 44.
3. Lower the GMU 44 into the rack and secure the plate with the three Phillips
screws.
Original GMU 44 is Reinstalled
If the original GMU 44 was reinstalled, then software loading is not required. This does
not include units that were returned for repair as their software and configuration files
are deleted during the repair testing process. Recalibration is required only if the
mount for the magnetometer was changed. If the magnetometer mount was changed,
refer to Section 5.6.2 of the G500H STC Installation Manual for the GRS 77H/GMU 44
Magnetic Calibration
.
New, Repaired or Exchange GMU 44 is Installed
If a new, repaired, or exchange GMU 44 unit is installed, then software must be loaded
and the GRS 77H/GMU 44 Magnetic Calibration must be performed. Refer to Section 5
of the G500H STC Installation Manual for instructions on software loading (5.4.3) and
Magnetic Calibration (5.6.2).
iii Return to Service
After removing and reinstalling the GMU 44, the following return-to-service checks
should be performed (reference Section 12-00-10 Return to Service Checks).
b) GDC 74H, Air Data Computer
i Removal
1. Access the GDC 74H, (reference Section 6-00-00, Dimensions and Access)
2. Disconnect the pitot/static plumbing from the rear of the unit. Disconnect the
single connector.
3. Remove the two (2) screws on the mounting plate near the pitot/static ports.
Loosen the other two (2) screws.
31-00-00