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

TASK 31-32-00-810-842-A
Loss of the Bus 3 Output from the ADIRU 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 313204
AMM 31-32-34-000-001	Removal of the CFDIU
AMM 31-32-34-400-001	Installation of the CFDIU

3. Fault Confirmation
Subtask 31-32-00-865-089-A

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

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
49VU	NAV PROBES/ADIRU3/PWR/SWTG	8FP	F09
** ON A/C NOT FOR ALL
49VU	NAV PROBES/ADIRU3/PWR/SWTG	8FP	F08
** ON A/C ALL
121VU	ADIRS/ADIRU/3PWR/SWTG	9FP	N09
121VU	ADIRS/ADIRU/3/26VAC AND AOA	5FP3	N07
121VU	ADIRS/ADIRU/3/115VAC	4FP3	N05
121VU	ADIRS/ADIRU/3/28VDC	6FP3	N03

Subtask 31-32-00-740-130-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 31-32-00-810-090-A

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

(1) If the fault continues:

do a check and repair the wiring from the CFDIU (1TW) pins AB/13F, 13G to the first terminal block , ASM 313204.

Subtask 31-32-00-740-131-A

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

[Rev.8 from Aug 2018] 2026.04.04 04:29:50 UTC