Loss of the BSCU Buses 1+2 of the SDAC 1

TASK 31-54-00-810-940-A
Loss of the BSCU Buses 1+2 of the SDAC 1

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 31-54-00-865-137-A

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

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C ALL
121VU	HYDRAULIC/BRAKING AND STEERING/SYS2/SPLY	4GG	M36
121VU	HYDRAULIC/BRAKING AND STEERING/SYS2/CTL	3GG	M35
121VU	HYDRAULIC/BRAKING AND STEERING/SYS1/CTL	1GG	M34
121VU	HYDRAULIC/BRAKING AND STEERING/SYS1/IND AND/SPLY	2GG	M33

Subtask 31-54-00-710-313-A

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

4. Fault Isolation
Subtask 31-54-00-810-189-A

A. If the test gives the maintenance message SDAC 1 : NO DATA FROM BSCU 1+2:

(1) If the fault continues:

do a check and repair as necessary the wiring from the SDAC 1 (1WV1)
. pins AB/14G, 14H to the first terminal block
. pins AE/14C, 14D to the first terminal block ASM 315403.

Subtask 31-54-00-710-314-A

B. Do the test given in Para. 3.

[Rev.8 from Aug 2018] 2026.04.04 04:30:33 UTC