Loss of the Bus Output from the FQIC to the CFDIU

TASK 31-32-00-810-821-A
Loss of the Bus Output from the FQIC to the CFDIU

1. Possible Causes

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 28-42-34-000-001	Removal of the Fuel Quantity-Indicating Computer (FQIC)
AMM 28-42-34-400-001	Installation of the Fuel Quantity-Indicating Computer (FQIC)
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 31-32-00-865-068-A

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

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C ALL
49VU	FUEL/FQI/CHAN/1	1QT	A13
121VU	FUEL/FQI/CHANNEL/1 AND 2	8QT	L26
121VU	FUEL/FQI/CHAN/2	2QT	M27

Subtask 31-32-00-740-088-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 31-32-00-810-069-A ** ON A/C NOT FOR ALL

A. If the test gives the maintenance message NO FQI DATA:

(1) If the fault continues:

(a) If the fault continues:

do a check and repair the wiring from the CFDIU (1TW) to the FQIC (3QT) from pins AA/5F, 5G to pins AB/12F, 13F , ASM 313204.

Subtask 31-32-00-810-069-B ** ON A/C NOT FOR ALL

A. If the test gives the maintenance message NO FQI DATA:

(1) If the fault continues:

(a) If the fault continues:

do a check and repair the wiring from the CFDIU (1TW) to the FQIC (3QT) from pins AA/5F, 5G to pins AB/8E, 8F ASM 313204.

Subtask 31-32-00-740-089-A

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

[Rev.8 from Aug 2018] 2026.04.04 04:29:49 UTC