Failure of the FMGC 1

TASK 22-11-00-810-801-A
Failure of the FMGC 1

1. Possible Causes

FMGC-1 [1CA1]
wiring of the 28VDC and 28VDC GND signals
short to ground between the circuit breaker (10CA1) and the A/THR 1 relays (5CA1), (17CA1) and (18CA1)
C/B-AUTO FLT/FMGC/1 [10CA1]

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
ASM 223101
AMM 22-83-34-000-001	Removal of the FMGC
AMM 22-83-34-400-001	Installation of the FMGC
ASM 228401
AMM 22-96-00-710-001	Operational Test of the AFS

3. Fault Confirmation
Subtask 22-11-00-865-068-A

A. Make sure that this(these) circuit breaker(s) is(are) closed:

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C ALL
49VU	AUTO FLT/FMGC/1	10CA1	B02

Subtask 22-11-00-710-050-A

B. Test
(1) Do the operational test of the AFS AMM 22-96-00-710-001 and read the result for the FMGC 1.
(a) If the circuit breaker (10CA1) is open, refer to Para. 4.B.

4. Fault Isolation
Subtask 22-11-00-810-050-A

A. If the circuit breaker (10CA1) is closed and if the test gives the maintenance message AFS : FMGC1:

remove the FMGC-1 [1CA1] AMM 22-83-34-000-001
do a check and repair the wiring of the 28VDC and 28VDC GND signals at the FMGC1 connector ASM 228401

(1) If the check is correct:

replace the FMGC-1 [1CA1] and AMM 22-83-34-400-001.

Subtask 22-11-00-810-076-A

B. If the circuit breaker (10CA1) is open:

close this circuit breaker.

(1) If the circuit breaker (10CA1) trips:

replace the FMGC-1 [1CA1] AMM 22-83-34-000-001 and AMM 22-83-34-400-001.

(a) If the fault continues:

do a check for a short to ground between the circuit breaker (10CA1) and the FMGC 1 (1CA1) ASM 228401
do a check for a short to ground between the circuit breaker (10CA1) and the A/THR 1 relays (5CA1), (17CA1) and (18CA1) ASM 223101.

1 If there is a short to ground:

repair the above wirings.

2 If there is no short to ground:

replace the C/B-AUTO FLT/FMGC/1 [10CA1] .

Subtask 22-11-00-710-051-A

C. Do the test given in Para. 3.

[Rev.8 from Aug 2018] 2026.04.04 04:25:06 UTC