loss of the Feedback Bus from the Lower ECAM DU to the DMC 1

TASK 31-63-82-810-852-A
loss of the Feedback Bus from the Lower ECAM DU to the DMC 1

1. Possible Causes

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 31-60-00-720-002	Operational Test of the DMC/DU data bus
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 31-63-82-720-050-A ** ON A/C NOT FOR ALL

A. Test
Do the operational test of DMC/DU data bus AMM 31-60-00-720-002.

4. Fault Isolation
Subtask 31-63-82-810-135-A ** ON A/C NOT FOR ALL

A. If the test gives the maintenance message DU SD(4WT2)/DMC1(1WT1):

(1) If the fault continues:

remove the DMC 1
remove the DU-ECAM, LOWER [4WT2] AMM 31-63-22-000-001
do a check and repair the aircraft wiring of the DSDL ECAM FDBK bus from the LOWER ECAM-DU pins AA/23, 24 to the DMC 1 pins AB/11D, 11E ASM 316104.
install the DU-ECAM, LOWER [4WT2] AMM 31-63-22-400-001
install the DMC 1.

5. Close-up
Subtask 31-63-82-720-051-A ** ON A/C NOT FOR ALL

A. Do the test given in Para. 3.

[Rev.8 from Aug 2018] 2026.04.04 04:31:17 UTC