Loss of the ARINC 429 Data between the FWC 1 and the CFDIU

TASK 31-32-00-810-915-A
Loss of the ARINC 429 Data between the FWC 1 and the CFDIU

1. Possible Causes

CFDIU [1TW]
wiring

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 31-32-00-740-003	Ground Scanning of the CFDIU
AMM 31-32-00-869-002	Procedure for the Class 3 Fault Reading
AMM 31-32-34-000-001	Removal of the CFDIU
AMM 31-32-34-400-001	Installation of the CFDIU
ASM 315205

3. Fault Confirmation
Subtask 31-32-00-865-140-A

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

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C ALL
49VU	FWS/FWC1/SPLY	3WW	F01

Subtask 31-32-00-740-232-A

B. Test
On the CFDS MENU page, get access to the AVIONICS STATUS page AMM 31-32-00-869-002.
If the fault is not confirmed, do the GROUND SCANNING of the CFDIU AMM 31-32-00-740-003.

4. Fault Isolation
Subtask 31-32-00-810-143-A

A. If the test gives the maintenance message:
NO FWC 1 DATA

replace the CFDIU [1TW] , AMM 31-32-34-000-001 and AMM 31-32-34-400-001.

(1) If the fault continues:

do a check and repair the wiring from the CFDIU (1TW) pins AA/5D, 5E to the first terminal block , ASM 315205.

Subtask 31-32-00-740-233-A

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

[Rev.8 from Aug 2018] 2026.04.04 04:29:57 UTC