Failure of One of the 6 DUs Detected by the DMC3

TASK 31-63-81-810-809-A
Failure of One of the 6 DUs Detected by the DMC3

1. Possible Causes

PFD-CAPT [2WT1]
wiring
DMC-3 [1WT3]
ND-CAPT [3WT1]
DU-ECAM, UPPER [4WT1]
PFD-F/O [2WT2]
ND-F/O [3WT2]
DU-ECAM, LOWER [4WT2]

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 31-60-00-740-002	Perform Electronic Instrument System (EIS) Input Test
ASM 316104
AMM 31-63-22-000-001	Removal of the Display Unit
AMM 31-63-22-400-001	Installation of the Display Unit
AMM 31-63-34-000-001	Removal of the DMC
AMM 31-63-34-400-001	Installation of the DMC

3. Fault Confirmation
Subtask 31-63-81-740-066-A ** ON A/C NOT FOR ALL

A. Test
Do the EIS input test AMM 31-60-00-740-002.

4. Fault Isolation
Subtask 31-63-81-810-060-A ** ON A/C NOT FOR ALL

A. With the EIS DMC selector switch (18WT) on the SWITCHING panel (8VU) at CAPT/3.
(1) If the test gives the maintenance message DMC3 : RECONF WIRING and there is no CAPT PFD image:

replace the PFD-CAPT [2WT1] AMM 31-63-22-000-001 and AMM 31-63-22-400-001.

(a) If the fault continues:

do a check of the wiring from the CAPT PFD (2WT1) to the DMC1 (1WT1):
. pins AA/21, 22 to pins AB/10B, 10C
. pins AA/23, 24 to pins AB/10D, 10E ASM 316104.

1 If there is no continuity:

repair the wiring.

2 If there is continuity:

do a check and repair the wiring from the DMC1 (1WT1) to the DMC3 (1WT3):
. pins AB/10F, 10G to pins AB/9D, 9E
. pins AB/10H, 10J to pins AB/9B, 9C ASM 316104.

a If the fault continues:

replace the DMC-3 [1WT3] AMM 31-63-34-000-001 and AMM 31-63-34-400-001.

(2) If the test gives the maintenance message DMC3 : RECONF WIRING and there is no CAPT ND image:

replace the ND-CAPT [3WT1] AMM 31-63-22-000-001 and AMM 31-63-22-400-001.

(a) If the fault continues:

do a check of the wiring from the CAPT ND (3WT1) to the DMC1 (1WT1):
. pins AA/21, 22 to pins AB/9B, 9C
. pins AA/23,24 to pins AB/9D, 9E ASM 316104.

1 If there is no continuity:

repair the wiring.

2 If there is continuity:

do a check and repair the wiring from the DMC1 (1WT1) to the DMC3 (1WT3):
. pins AB/9H, 9J to pins AB/10B, 10C
. pins AB/9F, 9G to pins AB/10D, 10E ASM 316104.

a If the fault continues:

replace the DMC-3 [1WT3] AMM 31-63-34-000-001 and AMM 31-63-34-400-001.

(3) If the test gives the maintenance message DMC3 : RECONF WIRING and there is no upper ECAM DU image:

replace the DU-ECAM, UPPER [4WT1] AMM 31-63-22-000-001 and AMM 31-63-22-400-001.

(a) If the fault continues:

do a check of the wiring from the upper ECAM DU (4WT1) to the DMC1 (1WT1):
. pins AA/35, 36 to pins AB/11B, 11C
. pins AA/38, 39 to pins AB/11D, 11E ASM 316104.

1 If there is no continuity:

repair the wiring.

2 If there is continuity:

do a check and repair the wiring from the DMC1 (1WT1) to the DMC3 (1WT3):
. pins AB/11F, 11G to pins AB/11D, 11E
. pins AB/11H, 11J to pins AB/11B, 11C ASM 316104.

a If the fault continues:

release the DMC-3 [1WT3] AMM 31-63-34-000-001 and AMM 31-63-34-400-001.

Subtask 31-63-81-810-061-A ** ON A/C NOT FOR ALL

B. With the EIS DMC selector switch (18WT) on the SWITCHING panel (8VU) at F/O/3.
(1) If the test gives the maintenance message DMC3 : RECONF WIRING and there is no F/O PFD image:

replace the PFD-F/O [2WT2] AMM 31-63-22-000-001 and AMM 31-63-22-400-001.

(a) If the fault continues:

do a check of the wiring from the F/0 PFD (2WT2) to the DMC2 (1WT2):
. pins AA/21, 22 to pins AB/10B, 10C
. pins AA/23, 24 to pins AB/10D, 10E ASM 316104.

1 If there is no continuity:

repair the wiring.

2 If there is continuity:

do a check and repair the wiring from the DMC2 (1WT2) to the DMC3 (1WT3):
. pins AB/10F, 10G to pins AB/9D, 9E
. pins AB/10H, 10J to pins AB/9B, 9C ASM 316104.

a If the fault continues:

replace the DMC-3 [1WT3] AMM 31-63-34-000-001 and AMM 31-63-34-400-001.

(2) If the test gives the maintenance message DMC3 : RECONF WIRING and there is no F/0 ND image:

replace the ND-F/O [3WT2] AMM 31-63-22-000-001 and AMM 31-63-22-400-001.

(a) If the fault continues:

do a check of the wiring from the F/0 ND (3WT2) to the DMC2 (1WT2):
. pins AA/21, 22 to pins AB/9B, 9C
. pins AA/23, 24 to pins AB/9D, 9E ASM 316104.

1 If there is no continuity:

repair the wiring.

2 If there is continuity:

do a check and repair the wiring from the DMC2 (1WT2) to the DMC3 (1WT3):
. pins AB/9H, 9J to pins AB/10B, 10C
. pins AB/9F, 9G to pins AB/10D, 10E ASM 316104.

a If the fault continues:

replace the DMC-3 [1WT3] AMM 31-63-34-000-001 and AMM 31-63-34-400-001.

(3) If the test gives the maintenance message DMC3 : RECONF WIRING and there is no lower ECAM DU image:

replace the DU-ECAM, LOWER [4WT2] AMM 31-63-22-000-001 and AMM 31-63-22-400-001.

(a) If the fault continues:

do a check of the wiring from the lower ECAM DU (4WT2) to the DMC2 (1WT2):
. pins AA/35, 36 to pins AB/11B, 11C
. pins AA/38, 39 to pins AB/11D, 11E ASM 316104.

1 If there is no continuity:

repair the wiring.

2 If there is continuity:

do a check and repair the wiring from the DMC2 (1WT2) to the DMC3 (1WT3):
. pins AB/11F, 11G to pins AB/11D, 11E
. pins AB/11H, 11J to pins AB/11B, 11C ASM 316104.

a If the fault continues:

replace the DMC-3 [1WT3] AMM 31-63-34-000-001 and AMM 31-63-34-400-001.

Subtask 31-63-81-740-067-A ** ON A/C NOT FOR ALL

C. Do the test given in Para. 3.

[Rev.8 from Aug 2018] 2026.04.04 04:30:53 UTC