System Maintenance Manual

Page 5-34 G1000/GFC700 System Maintenance Manual – C90A/C90GT/C90GTi King Air
Revision F 190-00682-01
Shows the condition of various monitor board components.
SERVO PROGRAM (1-3):
Servo program discretes are used to determine the HW strapping for each
GSA to define the servo type. This information can be cross-referenced against the system interconnects
to verify proper servo grounding.
AP DISCONNECT:
Same as GIA Status.
PFT:
Indicates whether the pre-flight test has passed or failed.
HIGH RES & HIGH RNG LOAD CELL CAL:
Shows the condition of the high resolution and high range
load cells on the monitor board. An invalid data indicator box indicates a corrupt or missing load cell
calibration; return the servo to Garmin.
DRIVE SERVO
Allows the technician to enter a desired RPM at which to manually drive the selected servo. Direction of
rotation is controlled by the polarity of the RPM (+ or -). After the speed is entered, the technician may
use the ENG CLCH and DRV SRVO softkeys to drive the servo.
NOTE
Be especially certain that the flight controls are clear and safe to operate before manually driving the
servo.
SERVO DATA
Shows real-time reported data including servo voltage, speed, motor current, load cell torque, and clutch
solenoid status. A valid data indicator box indicates the servo clutch is engaged.
SLIP CLUTCH TEST RESULTS
This window is used during the automatic slip clutch torque measurement check.
5.6.4 GIA Fault Log Descriptions
The section was created to help determine why the GFC 700 has failed the Pre-Flight Test indicated by
the red PFT annunciation
, it defines the PFT sequence for the servos and the GFC 700
system and then provides troubleshooting information to help resolve failures.
There are 16 steps to the GFC 700 PFT. The PFT is performed by both GIA’s at startup, and needs to
pass on both GIA’s before the autopilot can be engaged.
The PFT is only started if the AHRS has aligned, the GIA’s and servos are configured and the
certification gains are valid. If the PFT has not completed after one minute from when the initialization
started, the PFT will fail. After the system PFT has passed, it will be performed again if a servo resets, if
the autopilot servo breaker is reset or the cross side GIA restarts it.
Generally, the PFT failure fault is logged in the GIA Maintenance Log and not in the Servo Maintenance
Logs unless the GIA log fault identifies a servo problem.
NOTE
Thoroughly understanding the operation of the G1000 system in Configuration mode is
recommended before starting this procedure. The GFC Status page may be used to check
the status of the servos and engage them to aid in troubleshooting
To access the GIA and GSA Maintenance Logs, perform the following steps –