Garmin G1000 Reference Manual page 198

SECTION 13 – ANNUNCIATIONS
& ALERTS
System Annunciation Comment
Display is not receiving altitude input from the air data computer.
Display is not receiving vertical speed input from the air data computer.
Display is not receiving valid heading input from AHRS.
Display is not receiving valid transponder information.
Different versions of GDU software are installed in the PFD and MFD. This
can also indicate different versions of navigation software are installed in the
PFD and MFD. In some circumstances, a cross-talk error between the PFD
and MFD can cause this annunciation.
'LOI' Indicates Loss of Integrity of GPS information. GPS information is
either not present or is invalid for navigation use. 'DR' may also be seen
indicating that GPS is in Dead Reckoning Mode. Note that AHRS utilizes GPS
inputs during normal operation. AHRS operation may be degraded if GPS
signals are not present (see AFMS).
A red 'X' through any other display field, such as engine instrumentation
Other Various Red X Indications
fields, indicates that the field is not receiving valid data.
Garmin G1000 Cockpit Reference Guide for the Cessna Nav III 190-00384-09 Rev. A
13-8