Loss of the PACK 1 CONT Bus or the ACSC1 Bus to the SDAC 1

TASK 31-54-00-810-905-A
Loss of the PACK 1 CONT Bus or the ACSC1 Bus to the SDAC 1

1. Possible Causes

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 21-61-34-000-001	Removal of the Pack Controller
AMM 21-61-34-000-002	Removal of the Air-Conditioning System Controller
AMM 21-61-34-400-001	Installation of the Pack Controller
AMM 21-61-34-400-002	Installation of the Air-Conditioning System Controller
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 31-54-00-865-123-A

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

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
122VU	AIR COND/PACK TEMP/CTL SYS1/1/115VAC	1HH	X22
122VU	AIR COND/PACK TEMP/CTL SYS1/1/28VDC	3HH	X21
122VU	AIR COND/PACK TEMP CTL SYS2/1/28VDC	4HH	Y19
122VU	AIR COND/PACK TEMP CTL SYS2/1/115VAC	2HH	Y18

Subtask 31-54-00-710-246-A

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

4. Fault Isolation
Subtask 31-54-00-810-154-A ** ON A/C NOT FOR ALL

A. If the test gives the maintenance message SDAC1 : NO DATA FROM PACK1 CONT:

(1) If the fault continues:

(2) If the fault continues:

do a check and repair the wiring from the SDAC 1 (1WV1) pins AB/13J, 13K to the first terminal block , ASM 315403.

Subtask 31-54-00-810-154-B ** ON A/C NOT FOR ALL

A. If the test gives the maintenance message:

SDAC1 : NO DATA FROM ACSC1

(1) If the fault continues:

(2) If the fault continues:

do a check and repair the wiring from the SDAC 1 (1WV1) pins AB/13J, 13K to the Air Conditioning System Controller 1 pins AA/7E, 7F, ASM 315403.

Subtask 31-54-00-710-247-A

B. Do the test given in Para. 3.B.

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