Fuel - P/BSW-FUEL/ACT/AUTO FAULT Legend/Light Failure

TASK 28-28-00-810-805-A
Fuel - P/BSW-FUEL/ACT/AUTO FAULT Legend/Light Failure

WARNING: OBEY THE FUEL SAFETY PROCEDURES.

1. Possible Causes

FQIC [3QT]
SWITCH-INDICATOR, ACT [24QH]
BOARD-ANN LT TEST & INTFC [2LP]
aircraft wiring

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
TSM TASK 28-28-00-810-804-A	Fuel - ACT Automatic Transfer Failure
TSM TASK 28-28-00-810-804-A-01	Fuel - ACT Automatic Transfer Failure (802VU ACT Relay Testbox)
AMM 28-28-00-710-004	Operational Test of the ACT Automatic Transfer System
AWM 282802
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 33-14-33-000-001	Removal of the Annunciator-Light Test and Interface-Board
AMM 33-14-33-400-001	Installation of the Annunciator-Light Test and Interface-Board

3. Fault Confirmation
Subtask 28-28-00-710-054-C ** ON A/C NOT FOR ALL

A. Test
(1) During the operation of the ACT automatic transfer system the P/BSW-FUEL/ACT/AUTO (24QH) FAULT legend is a configuration warning.

NOTE: With the P/BSW (24QH) in the automatic (out) position, the FAULT can be given. The fault cannot be given during refuel.
With the P/BSW (24QH) in the FWD/manual (in) position the FAULT legend changes its function and shows ACT fuel pump low pressure.

In ACT automatic transfer the FAULT legend function is activated simultaneously with the ECAM warning FUEL - ACT XFR FAULT.

NOTE: This ECAM warning is only given in certain flight phases, and is controlled by the FWC.

The above indications are given because the fuel load distribution is not correct or the fuel has not been used in the correct sequence.

The warnings will be activated if the fuel distribution is as follows:

the center tank, less than 2950 kg (6500 lb) AND the ACT1, more than 300 kg (660 lb) AND/OR the ACT2, more than 300 kg (660 lb).

The warnings will be reset if the fuel distribution is as follows:

the center tank, more than 3000 kg (6610 lb) OR the ACT1, less than 250 kg (550 lb) AND ACT2, less than 250 kg (550 lb).

The source of the comparison logic which activates and resets this warning is contained in the FQIC(3QT).
The FQIC warning/FAULT logic output is:

activated if the conditions continue for more than 60 seconds
reset immediately.

This FQIC logic is inhibited during refuel.

The FQIC warning/FAULT logic output is transmitted on:

two (2) ARINC bus lines to the FWC (ECAM)
one (1) discrete signal line to the P/BSW-FUEL/ACT/AUTO (24QH), FAULT legend.

(2) Do the Operational Test of the ACT Automatic Transfer System AMM 28-28-00-710-004.
(3) If an ACT autofeed system failure is found:

do the ACT Automatic Transfer Failure (Ref. TSM TASK 28-28-00-810-804).

(4) If the P/BSW-FUEL/ACT/AUTO (24QH) FAULT legend,
operates as specified in the AMM Test:

maintenance steps are not necessary.

4. Fault Isolation
Subtask 28-28-00-810-054-A ** ON A/C NOT FOR ALL

A. Procedure
(1) If the P/BSW-FUEL/ACT/AUTO (24QH) FAULT legend,
does not operate as specified in the AMM Test:
(a) Replace the FQIC [3QT] AMM 28-42-34-000-001 and AMM 28-42-34-400-001.
(b) Do the test given in Para. 3.A.
(2) If the fault continues, do a check of AWM 282802 and replace, if necessary:
(a) The SWITCH-INDICATOR, ACT [24QH] .
(b) The BOARD-ANN LT TEST & INTFC [2LP] AMM 33-14-33-000-001 and AMM 33-14-33-400-001.
(c) Do the test given in Para. 3.A.
(3) If the fault continues, do a check of the aircraft wiring AWM 282802 between:

the FQIC (3QT) rack connector AC, pin 7A and the P/BSW-FUEL/ACT/AUTO (24QH), terminal B2 (FAULT ground wire)
the P/BSW-FUEL/ACT/AUTO (24QH) terminal B3 and BOARD-ANN LT & TEST (2LP) rack connector A, pin 34 (FAULT ground wire)
the BOARD-ANN LT & TEST (2LP) rack connector A, pin 35 and the C/B-ACT1/XFR VALVE/AUTO CTL (9QH), terminal 2 (28VDC supply).

(a) Repair all the unserviceable wiring and connectors.
(b) Do the test given in Para. 3.A.

[Rev.8 from Aug 2018] 2026.04.04 04:28:51 UTC