Loss of the AP1 ENGD Feedback Discretes

TASK 22-11-00-810-815-A
Loss of the AP1 ENGD Feedback Discretes

1. Possible Causes

FMGC-1 [1CA1]
FWC-1 [1WW1]
FWC-2 [1WW2]
ELAC-1 [2CE1]
FCU [2CA]
FAC-1 [1CC1]
RELAY-TAKEOVER & PRIORITY 1 [47CE1]
wiring of the AP OWN ENGD MON OWN discrete (from the FMGC 1 (1CA1) pin AE/3E to the FMGC 1 (1CA1) pin AE/12G)
wiring of the AP OWN ENGD COM OWN discrete (from the FMGC 1 (1CA1) pin AB/3E to the FMGC 1 (1CA1) pin AB/10D)
wiring of the AP OWN ENGD MON OPP discrete (from the FMGC 1 (1CA1) pin AE/3G to the FMGC 1 (1CA1) pin AD/14D)
wiring of the AP OWN ENGD COM OPP discrete (from the FMGC 1 (1CA1) pin AB/3G to the FMGC 1 (1CA1) pin AA/14B)
wiring of the AP INST DISC NO discrete (from the FMGC 1 (1CA1) pin AB/5C to the first terminal block)
wiring of the AP INST DISC NC discrete (from the FMGC 1 (1CA1) pin AB/1H to the first terminal block)

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 22-66-34-000-002	Removal of the FAC
AMM 22-66-34-400-002	Installation of the FAC
AMM 22-81-12-000-001	Removal of the FCU
AMM 22-81-12-400-001	Installation of the FCU
AMM 22-83-34-000-001	Removal of the FMGC
AMM 22-83-34-400-001	Installation of the FMGC
ASM 228503
AMM 22-96-00-710-001	Operational Test of the AFS
AMM 27-93-34-000-001	Removal of the ELAC
AMM 27-93-34-400-001	Installation of the ELAC
AMM 31-53-34-000-001	Removal of the Flight Warning Computer (FWC)
AMM 31-53-34-400-001	Installation of the Flight Warning Computer (FWC)

3. Fault Confirmation
Subtask 22-11-00-710-066-A

A. Test
(1) On the FCU, push the AP1 pushbutton switch.
(2) Do the operational test of the AFS AMM 22-96-00-710-001 and read the result for the FMGC 1.

4. Fault Isolation
Subtask 22-11-00-810-064-A

A. If the test gives the maintenance message AFS: FMGC1/AP ENGD FDBK:

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

(1) If the fault continues:

Remove the FWC 1 AMM 31-53-34-000-001.
Open the circuit breaker (10CA1) and after 5 seconds close it.
Wait approximately 2 minutes and do the operational test of the AFS AMM 22-96-00-710-001 and read the result for the FMGC 1.

(a) If the test gives the maintenance message AFS: FMGC1/AP ENGD FDBK:

Install the FWC 1 AMM 31-53-34-400-001.
Continue the troubleshooting.

(b) If the test does not give the maintenance message AFS: FMGC1/AP ENGD FDBK:

Install a new FWC-1 [1WW1] AMM 31-53-34-400-001.

(2) If the fault continues:

Remove the FWC 2 AMM 31-53-34-000-001.
Open the circuit breaker (10CA1) and after 5 seconds close it.
Wait approximately 2 minutes and do the operational test of the AFS AMM 22-96-00-710-001 and read the result for the FMGC 1.

(a) If the test gives the maintenance message AFS: FMGC1/AP ENGD FDBK:

Install the FWC 2 AMM 31-53-34-400-001.
Continue the troubleshooting.

(b) If the test does not give the maintenance message AFS: FMGC1/AP ENGD FDBK:

Install a new FWC-2 [1WW2] AMM 31-53-34-400-001.

(3) If the fault continues:

Remove the ELAC 1 AMM 27-93-34-000-001.
Open the circuit breaker (10CA1) and after 5 seconds close it.
Wait approximately 2 minutes and do the operational test of the AFS AMM 22-96-00-710-001 and read the result for the FMGC 1.

(a) If the test gives the maintenance message AFS: FMGC1/AP ENGD FDBK:

Install the ELAC 1 AMM 27-93-34-400-001
Continue the troubleshooting.

(b) If the test does not give the maintenance message AFS: FMGC1/AP ENGD FDBK:

Install a new ELAC-1 [2CE1] AMM 27-93-34-400-001.

(4) If the fault continues:

Replace the FCU [2CA] , AMM 22-81-12-000-001 and AMM 22-81-12-400-001.

(5) If the fault continues:

Replace the FAC-1 [1CC1] , AMM 22-66-34-000-002 AMM 22-66-34-400-002

(6) If the fault continues:

Replace the RELAY-TAKEOVER & PRIORITY 1 [47CE1] .

(7) If the fault continues:

Do a check and repair the wiring of the AP OWN ENGD MON OWN discrete (from the FMGC 1 (1CA1) pin AE/3E to the FMGC 1 (1CA1) pin AE/12G)
ASM 228503.
Do a check and repair the wiring of the AP OWN ENGD COM OWN discrete (from the FMGC 1 (1CA1) pin AB/3E to the FMGC 1 (1CA1) pin AB/10D)
ASM 228503.
Do a check and repair the wiring of the AP OWN ENGD MON OPP discrete (from the FMGC 1 (1CA1) pin AE/3G to the FMGC 1 (1CA1) pin AD/14D)
ASM 228503.
Do a check and repair the wiring of the AP OWN ENGD COM OPP discrete (from the FMGC 1 (1CA1) pin AB/3G to the FMGC 1 (1CA1) pin AA/14B)
ASM 228503.

(8) If the fault continues:

Do a check of the wiring of the AP INST DISC NO discrete (from the FMGC 1 (1CA1) pin AB/5C to the first terminal block)
Do a check and repair the wiring of the AP INST DISC NC discrete (from the FMGC 1 (1CA1) pin AB/1H to the first terminal block)
ASM 228503.

Subtask 22-11-00-710-067-A

B. Do the test given in Para. 3.

[Rev.8 from Aug 2018] 2026.04.04 04:25:07 UTC