Loss of the Feedback Bus from the Lower ECAM DU to the DMC 2

TASK 31-63-82-810-851-A
Loss of the Feedback Bus from the Lower ECAM DU to the DMC 2

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 316304
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 31-63-82-720-054-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 31-63-82-810-137-A ** ON A/C NOT FOR ALL

A. If the test gives the maintenance message DU SD(4WT2)/DMC2(1WT2):

(1) If the fault continues:

remove the DMC 2
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/38, 39 to the DMC 2 pins AB/11D, 11E ASM 316304.
install the DU-ECAM, LOWER [4WT2] AMM 31-63-22-400-001
install the DMC 2.

5. Close-up
Subtask 31-63-82-720-055-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