System Maintenance Manual

Page 5-20 G1000/GFC700 System Maintenance Manual – C90A/C90GT/C90GTi King Air
Revision G 190-00682-01
5.2.2 System Failure Troubleshooting
The following table provides basic troubleshooting guidance for LRU failures. Refer to G1000/GFC 700
Wiring Diagram, listed in Table 1-2, as needed to verify interconnects.
Invalid Data Field
Associated
LRU(s)
Solution
Low Speed Awareness Band
permanently displayed
GDU
NOTE
Reference Table 3-1 for interpretation of data
indicator symbols
• With aircraft weight on wheels and the G1000 in
Configuration Mode, check that the RH GEAR ON
GROUND Discrete In indication on GIA I/O
CONFIGURATION page is VALID or TRUE.
• If indication is VALID or TRUE, switch GIA1 and GIA2,
to verify location of problem:
 If problem is resolved, replace defective unit.
 If indication is INVALID or FALSE, check for wiring
faults between the GIAs and aircraft squat switch
system.
Low Speed Awareness Band
permanently inhibited
GDU
NOTE
Reference Table 3-1 for interpretation of data
indicator symbols
• With aircraft weight off wheels and the G1000 in
Configuration Mode, check that the RH GEAR ON
GROUND Discrete In indication on GIA I/O
CONFIGURATION page is INVALID or FALSE.
• If indication is INVALID or FALSE, switch GIA1 and
GIA2, to verify location of problem:
 If problem is resolved, replace unit.
 If indication is VALID or TRUE, check for wiring
faults between the GIAs and aircraft squat switch
system.
NAV1 & COM1
GIA1
• Check configuration settings for GIA1 and PFD1.
• Swap GIA1 and GIA2, to verify location of problem:
 If problem follows GIA1, replace GIA1.
• Check Ethernet interconnect from GIA1 to PFD1.
 If problem persists, replace PFD.
NAV2 & COM2
GIA2
• Check configuration settings for GIA2 and PFD2.
• Swap GIA1 and GIA2, to verify location of problem:
 If problem follows GIA2, replace GIA2.
• Check Ethernet interconnect from GIA2 to PFD2.
 If problem persists, replace PFD.