Garmin G300 Installation Manual page 75

e) Absence of mounting supports recommended by the aircraft manufacturer.
f) GSU 73 connector not firmly attached to unit.
g) Cabling leading to GSU 73 or GMU 44 not firmly secured to supporting structure.
h) An engine/propeller combination that is significantly out of balance.
In some aircraft, attempting the engine runup test on a day with very strong and/or gusty
winds may cause the test to occasionally fail. However, windy conditions should not be
taken as evidence that the test would pass in calm conditions; an actual pass is required
before the installation can be considered adequate.
10. After a few minutes the calibration will finish and a Done button will appear at the bottom of
the display, ensure that a ENGINE RUN-UP TEST PASSED message appears at the bottom
of the display, press the ENT Key to return to the GSU Status Page.
G300 Installation Manual – Post Installation Checkout and Calibration Procedures
190-00921-01
NOTE
Page 9-19
Revision A