W DOC AIRBUS | TSM A320F

Failure of the Ground/Flight signal Between the GAPCU and the LGCIU

TASK 24-41-00-810-817-A
Failure of the Ground/Flight signal Between the GAPCU and the LGCIU

1. Possible Causes
  • GAPCU [24XG]
  • wiring
2. Job Set-up Information
 A. Referenced Information
REFERENCE
DESIGNATION
AMM 24-41-00-740-002
Operational Check of the GAPCU via the CFDS
ASM 244101
AMM 24-41-34-000-001
Removal of the Ground Power Control Unit (GPCU)
AMM 24-41-34-400-001
Installation of the Ground Power Control Unit (GPCU)
3. Fault Confirmation
Subtask 24-41-00-740-060-B ** ON A/C NOT FOR ALL
A. Test
   (1) Do the trouble shooting for all CFDS messages related to the Chapter 32 or to the LGCIU that can come into view with the CFDS message LGCIU (5GA1)/GAPCU (24XG).
NOTE: You can ignore this CFDS message if it comes into view when the aircraft is on jacks for maintenance or when you remove the power from the LGCIU 1 when the aircraft is on the ground.
     (a) If there are no Chapter 32 or LGCIU-related CFDS messages, or if the fault continues after the trouble shooting:
       1 If the BITE test gives the message TEST FAILED:
  • do the trouble shooting given in Para 4.A.
       2 If the BITE test gives the message TEST PASSED:
  • do the trouble shooting given in Para 4.B.
4. Fault Isolation
Subtask 24-41-00-810-085-A ** ON A/C NOT FOR ALL
A. If the BITE test gives the message TEST FAILED:
  • push the line key adjacent to the TEST FAILED message.
   (1) If the maintenance message GAPCU (24XG) comes into view:
Subtask 24-41-00-810-068-A ** ON A/C NOT FOR ALL
B. If the BITE test gives the message TEST PASSED:
  • do a check of the wiring of the ground/flight signal ASM 244101 between pin B/9E of the LGCIU (5GA1) and pin A/2C of the GAPCU (24XG).
   (1) If there is no continuity:
  • repair or replace as necessary.
   (2) If there is continuity:
Subtask 24-41-00-740-061-A ** ON A/C NOT FOR ALL
C. Do the test given in Para. 3.
[Rev.8 from Aug 2018] 2026.04.04 04:26:54 UTC
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