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

TASK 31-53-00-810-812-A
Loss of the ARINC 429 Data between the FWC 1 and the CFDIU

1. Possible Causes

FWC-1 [1WW1]
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
ASM 315205
AMM 31-53-34-000-001	Removal of the Flight Warning Computer (FWC)
AMM 31-53-34-400-001	Installation of the Flight Warning Computer (FWC)

3. Fault Confirmation
Subtask 31-53-00-865-055-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 31-53-00-740-060-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 31-53-00-810-061-A

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

replace the FWC-1 [1WW1] , AMM 31-53-34-000-001 and AMM 31-53-34-400-001.

(1) If the fault continues:

do a check and repair the wiring from the FWC 1 (1WW1) pins AB/12J, 12K to the first terminal block ASM 315205.

Subtask 31-53-00-740-061-A

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

[Rev.8 from Aug 2018] 2026.04.04 04:30:12 UTC