Loss of the SFCC 1 and SFCC 2 Buses of the SDAC 1

TASK 31-54-00-810-938-A
Loss of the SFCC 1 and SFCC 2 Buses 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 31-54-00-865-135-A

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

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C ALL
49VU	FLIGHT CONTROLS/SLT FLP/POS/IND 1	1CN	B12
49VU	FLIGHT CONTROLS/FLP/CTL AND MONG/SYS1	6CV	B07
49VU	FLIGHT CONTROLS/SLT/CTL AND MONG/SYS1	5CV	B06
105VU	ELEC/HOT BUS/702PP SPLY	5PB2	D02
105VU	ELEC/HOT BUS/701PP SPLY	5PB1	D01
105VU	ELEC/HOT BUS/702PP SPLY	12PB2	E02
105VU	ELEC/HOT BUS/701PP SPLY	12PB1	E01
121VU	FLIGHT CONTROLS/SLT FLP/2POS/IND	2CN	P16
121VU	FLIGHT CONTROLS/FLP/CTL AND/MONG/SYS2	8CV	Q21
121VU	FLIGHT CONTROLS/SLT/CTL/SYS2	7CV	R21

Subtask 31-54-00-710-309-A

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

4. Fault Isolation
Subtask 31-54-00-810-187-A

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

(1) If the fault continues:

do a check and repair as necessary the wiring from the SDAC 1 (1WV1)
. pins AB/11J, 11K to the first terminal block
. pins AE/11A, 11B to the first terminal block ASM 315403.

Subtask 31-54-00-710-310-A

B. Do the test given in Para. 3.

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