G900X/G950 Installation and Maintenance Manual – Software, Configuration, and Calibration
Page 15-45
190-00719-00
Revision D
NOTE
Should a failure occur, the technician may perform the Engine Run-up test up to 3 times
successively before corrective action must be taken. If the test does not pass after three
attempts, then the installation should not be considered reliable until the source of the
vibration problem is identified and remedied. In the event of repeated failure of the
engine run-up test, record the values that are reported to be out of range for future
reference.
The following are potential causes for failure of the engine run-up test:
a)
Vibration motion of GRS77 and/or GMU44 caused by neighboring equipment
and/or supports.
b)
Mounting screws and other hardware for GRS77 and/or GMU44 not firmly
attached.
c)
GRS77 connector not firmly attached to unit.
d)
Cabling leading to GRS77 or GMU44 not firmly secured to supporting structure.
e)
An engine / propeller that is significantly out of balance.
5.
Press the ENT key on the PFD to conclude this procedure.
15.4.3.6 Procedure D: Magnetometer Interference Test
A magnetometer interference test verifies a magnetically ‘clean’ installation of the GMU 44. This test
exercises various devices on the aircraft that could potentially affect the magnetic field as measured by
the GMU 44 .
Figure 15-31. Magnetometer Interference Test
NOTE
This test is used to validate that no electronic device interferes with the operation of the
GMU 44 magnetometer. Calibration Procedures A through C are not required prior to
this procedure.
