Loss of the Bus Output from the DMC 3 to the CFDIU

TASK 31-32-00-810-878-A
Loss of the Bus Output from the DMC 3 to the CFDIU

1. Possible Causes

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 31-32-00-869-002	Procedure for the Class 3 Fault Reading
ASM 313205
AMM 31-32-34-000-001	Removal of the CFDIU
AMM 31-32-34-400-001	Installation of the CFDIU
AMM 31-63-34-000-001	Removal of the DMC
AMM 31-63-34-400-001	Installation of the DMC

3. Fault Confirmation
Subtask 31-32-00-865-126-A

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

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C ALL
49VU	EIS/DMC3/SWTG	21WT3	E07
121VU	EIS/DMC3/SPLY	10WT3	Q09

Subtask 31-32-00-740-200-A

B. Test
On the CFDS MENU page, get access to the AVIONICS STATUS page AMM 31-32-00-869-002.

4. Fault Isolation
Subtask 31-32-00-810-127-A ** ON A/C NOT FOR ALL

A. If the test gives the maintenance message NO DMC 3 DATA:

(1) If the fault continues:

(2) If the fault continues:

do a check and repair the wiring from the CFDIU (1TW) to the DMC 3 (1WT3) from pins AA/2H, 2J to pins AB/1C, 1D ASM 313205.

Subtask 31-32-00-810-127-C ** ON A/C NOT FOR ALL

A. If the test gives the maintenance message NO DMC 3 DATA:

(1) If the fault continues:

(2) If the fault continues:

do a check and repair the wiring from the CFDIU (1TW) to the DMC 3 (1WT3) from pins AA/2H, 2J to pins AD/13F, 13E ASM 313205.

Subtask 31-32-00-740-201-A

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

[Rev.8 from Aug 2018] 2026.04.04 04:29:54 UTC