System Maintenance Manual

G1000/GFC700 System Maintenance Manual – C90A/C90GT/C90GTi King Air Page 5-21
190-00682-01 Revision F
Invalid Data Field
Associated
LRU(s)
Solution
GPS LOI
GIA1 or GIA2
• Ensure that a cell phone or a device using cell phone
technology is not turned on (even in a monitoring state)
in the cabin.
• Check GPS1 and GPS2 signal strength on AUX
page 4. Refer to GIA GPS section if GPS cannot
acquire a position lock for troubleshooting.
• Check corresponding GPS antenna and cable for
faults.
• Check Ethernet interconnect between the PFD1 to
GIA1 or PFD2 to GIA2 for faults.
• Swap GIA1 and GIA2, to verify location of problem:
9 If problem follows the GIA, replace the GIA.
9 If problem persists, replace the PFD1 or PFD2.
XPDR FAIL
GTX 33
• Check GTX 33 configuration settings for GIA1 and
GIA2.
• Check GTX 33/GIA1 interconnect.
• Check GTX 33/GIA2 interconnect.
• Perform a SET>ACTV configuration reset on the GTX
Config page for each GTX, and verify the aircraft
registration is present.
• Replace GTX 33.
9 If problem persists, replace GIA.
TAS FAIL
AIRSPEED FAIL
ALTITUDE FAIL
VERT SPEED FAIL
GDC 74B
9 Inspect GDC 74B pitot/static plumbing integrity.
9 Inspect pitot/static ports and associated equipment for
faults.
9 For TAS failure, also check GTP 59 probe.
9 Check GDC 74B configuration settings for the PFDs,
MFD, GIA1, and GIA2.
1. If PFDs, MFD, and GIA configuration settings are
correct, replace the GDC configuration module.
9 If problem persists, replace the GDC 74B.
OAT
GTP 59
• Check OAT probe wiring and connectors for faults.
• Check GDC config module wiring for damage, replace
if any is found.
• Replace GDC config module
• Replace GDC 74B with a known good unit:
9 If problem persists, replace the GTP 59.