Loss of the Reception of the PS SPLIT Discrete by one FMGC

TASK 22-83-00-810-863-A
Loss of the Reception of the PS SPLIT Discrete by one FMGC

1. Possible Causes

FMGC-1 [1CA1]
wiring of the PS SPLIT discrete of the FMGC 1 (1CA1)
FMGC-2 [1CA2]
wiring of the PS SPLIT discrete of the FMGC 2 (1CA2)
BTC-1 [11XU1]
BTC-2 [11XU2]
CNTOR-DC NORM BUS 2 SWITCHING [1PC2]

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 22-83-34-000-001	Removal of the FMGC
AMM 22-83-34-400-001	Installation of the FMGC
ASM 228504
AMM 22-91-00-710-001	Ground Scanning of the AFS
AMM 24-22-55-000-001	Removal of the Contactors
AMM 24-22-55-400-002	Installation of the Contactors

3. Fault Confirmation
Subtask 22-83-00-860-058-A

A. Job set-up
(1) Aircraft Maintenance Configuration
(a) On the ELEC panel 35VU, make sure that the AVAIL legend of the EXT PWR pushbutton switch is on.

Subtask 22-83-00-710-158-A

B. Test
(1) Do the Ground Scanning of the AFS AMM 22-91-00-710-001.

NOTE: If Post Flight Report (PFR) fault message AFS:28V PWR 11XU1 is recorded during flight phase 02 (engine start-up) or flight phase 09 or 10 (engine shutdown), no maintenance action is necessary.

4. Fault Isolation
Subtask 22-83-00-810-144-A

A. If the test gives the maintenance message AFS : 28V PWR 11XU1:

push the line key adjacent to the RETURN indication until the AFS MAIN MENU page comes into view
push the line key adjacent to the TROUBLE SHOOTING DATA indication
push the line key adjacent to the FG1 COM indication, then FG2 COM indication
make sure that there is a snapshot related to an event 7
if this snapshot is present:
. make sure that the second number of the word W2 is equal to one of these values (on the FG1 COM and FG2 COM channels):
* 2, 4, 6, 8, A, C or E.

(1) If the second number is equal to 2, 4, 6, 8, A, C or E (on the FG1 COM channel only):

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 ground signal at the FMGC 1 (1CA1) pin AB/3B ASM 228504.

1 If there is no ground signal:

do a check and repair the wiring of the PS SPLIT discrete of the FMGC 1 (1CA1):
. from FMGC 1 (1CA1) pin AB/3B to BTC 1 (11XU1) pin B/26
. from BTC 1 (11XU1) pin B/28 to BTC 2 (11XU2) pin B/26
. from BTC 2 (11XU2) pin B/28 to connector (1PC2) pin B/16
. from the ground point to connector (1PC2) pin B/14 ASM 228504.

(2) If the second number is equal to 2, 4, 6, 8, A, C or E (on the FG2 COM channel only):

replace the FMGC-2 [1CA2] AMM 22-83-34-000-001 and AMM 22-83-34-400-001.

(a) If the fault continues:

do a check for a ground signal at FMGC 2 (1CA2) pin AB/3B ASM 228504.

1 If there is no ground signal:

do a check and repair the wiring of the PS SPLIT discrete of the FMGC 2 (1CA2):
. from FMGC 2 (1CA2) pin AB/3B to BTC 1 (11XU1) pin B/30
. from BTC 1 (11XU1) pin B/32 to BTC 2 (11XU2) pin B/30
. from BTC 2 (11XU2) pin B/32 to connector (1PC2) pin B/20
. from the ground point to connector (1PC2) pin B/18 ASM 228504.

(3) If the second number is equal to 2, 4, 6, 8, A, C or E (on the FG1 COM and on the FG2 COM channels):

replace the BTC-1 [11XU1] AMM 24-22-55-000-001 and AMM 24-22-55-400-002.

(a) If the fault continues:

replace the BTC-2 [11XU2] AMM 24-22-55-000-001 and AMM 24-22-55-400-002.

1 If the fault continues:

replace the CNTOR-DC NORM BUS 2 SWITCHING [1PC2] .

Subtask 22-83-00-710-159-A

B. Do the test given in Para. 3.

[Rev.8 from Aug 2018] 2026.04.04 04:25:33 UTC