Loss of the BMC 1 Bus of the SDAC 2

TASK 31-54-00-810-856-A
Loss of the BMC 1 Bus of the SDAC 2

1. Possible Causes

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 31-50-00-710-001	Ground Scanning of the Central Warning System
ASM 315403
AMM 31-55-34-000-001	Removal of the SDAC
AMM 31-55-34-400-001	Installation of the SDAC

3. Fault Confirmation
Subtask 31-54-00-865-095-A

A. Make sure that this(these) circuit breaker(s) is(are) closed:

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
49VU	AIR BLEED/ENG 1/CTL	3HA1	D12
49VU	AIR BLEED/ENG 1/MONG	2HA1	D11
** ON A/C NOT FOR ALL
49VU	AIR BLEED/ENG 1/CTL	2HA1	D11
122VU	AIR BLEED/ENG 1/MONG	3HA1	Z23

Subtask 31-54-00-710-148-A

B. Test
Do the ground scanning of the central warning systems AMM 31-50-00-710-001.

4. Fault Isolation
Subtask 31-54-00-810-105-A

A. If the test gives the maintenance message SDAC2 : NO DATA FROM BMC1:

(1) If the fault continues:

do a check and repair the wiring from the SDAC 2 (1WV2) pins AB/12G, 12H to the first terminal block , ASM 315403.

Subtask 31-54-00-710-149-A

B. Do the test given in Para. 3.

[Rev.8 from Aug 2018] 2026.04.04 04:30:27 UTC