DOC AIRBUS | TSM A320FFuel LP Fuel Valve Engine 1 Operates Slowly In Both Directions
TASK 28-24-00-810-809-A
Fuel LP Fuel Valve Engine 1 Operates Slowly In Both Directions
A. Fixtures, Tools, Test and Support Equipment
B. Referenced Information
3. Fault Confirmation
Subtask 28-24-00-710-056-A
Subtask 28-24-00-810-058-A
Subtask 28-24-00-860-052-A
[Rev.8 from Aug 2018]
2026.04.04 04:28:42 UTC
Fuel LP Fuel Valve Engine 1 Operates Slowly In Both Directions
WARNING:
OBEY THE FUEL SAFETY PROCEDURES.
WARNING:
WHEN YOU DO WORK ON THE FUEL SYSTEM WIRING, YOU MUST USE TEST EQUIPMENT THAT IS APPROVED (REFER TO INTERNATIONAL OR NATIONAL SPECIFICATIONS FOR INTRINSICALLY SAFE TEST EQUIPMENT: EN50020, UL913 OR EQUIVALENT). TEST EQUIPMENT THAT IS NOT APPROVED CAN CAUSE FIRE OR AN EXPLOSION.
1. Possible Causes- aircraft wiring
- ACTUATOR-LP FUEL VALVE, ENG 1 [9QG]
- VALVE-LP FUEL, ENG 1 [12QM]
- ENG/APU FIRE PNL [1WD]
- C/B-FUEL/LP VALVE/MOT1/ENG1 [1QG]
- C/B-FUEL/LP VALVE/MOT2/ENG1 [3QG]
A. Fixtures, Tools, Test and Support Equipment
| REFERENCE | QTY | DESIGNATION |
|---|---|---|
| No specific | AR | MULTIMETER - STANDARD |
| REFERENCE | DESIGNATION |
|---|---|
| ESPM 2053210 | |
| AMM 26-12-00-00- | |
| AMM 26-12-12-000-001 | Removal of the ENG/APU Fire Panel |
| AMM 26-12-12-400-001 | Installation of the ENG/APU Fire Panel |
| AMM 26-21-00-00- | |
| ASM 262102 | |
| AMM 28-24-00-00- | |
| ASM 282401 | |
| AWM 282401 | |
| AMM 28-24-41-000-001 | Removal of the LP Fuel Valve |
| AMM 28-24-41-400-001 | Installation of the LP Fuel Valve |
| AMM 28-24-51-000-001 | Removal of the LP Fuel Valve Actuator |
| AMM 28-24-51-400-001 | Installation of the LP Fuel Valve Actuator |
| AMM 76-12-00-00- | |
| ASM 761201 | |
| AWM 940502 | |
| TSM TASK 28-24-00-03 | ENGINE LP FUEL SHUT OFF - TASK SUPPORTING DATA |
Subtask 28-24-00-710-056-A
A. Test
(1) On the ENG/APU FIRE PANEL (1WD) located on the overhead panel 20VU, make sure that the ENG 1 FIRE PUSH pushbutton switch (P/BSW) is in the closed and guarded position.
(2) On the ECAM Control Panel 11VU, push (in) the FUEL P/BSW to get the FUEL system page on the ECAM lower display unit (DU).
(3) Make sure the ENG/MASTER 1 (3KC) switch (panel 115VU) is set to OFF.
(4) On the FUEL system page make sure the ENG 1 LP fuel valve symbol shows that the valve is closed (amber crossline).
(5) Make a note of the valve transit time for the following actions:
(b) Make sure the ENG 1 LP fuel valve symbol changes to open (green in-line).
(6) Make a note of the valve transit time for the following actions:
(b) Make sure the ENG 1 LP fuel valve symbol changes to closed (amber crossline).
(7) If the ENG 1 LP fuel valve:
4. Fault Isolation(1) On the ENG/APU FIRE PANEL (1WD) located on the overhead panel 20VU, make sure that the ENG 1 FIRE PUSH pushbutton switch (P/BSW) is in the closed and guarded position.
(2) On the ECAM Control Panel 11VU, push (in) the FUEL P/BSW to get the FUEL system page on the ECAM lower display unit (DU).
(3) Make sure the ENG/MASTER 1 (3KC) switch (panel 115VU) is set to OFF.
(4) On the FUEL system page make sure the ENG 1 LP fuel valve symbol shows that the valve is closed (amber crossline).
(5) Make a note of the valve transit time for the following actions:
NOTE: The LP fuel valve symbol shows a 45 degree amber line while in transit.
(a) Set the ENG/MASTER 1 (3KC) switch (panel 115VU) to ON, and immediately observe the ENG 1 LP fuel valve symbol on the FUEL system page. (b) Make sure the ENG 1 LP fuel valve symbol changes to open (green in-line).
(6) Make a note of the valve transit time for the following actions:
NOTE: The LP fuel valve symbol shows a 45 degree amber line while in transit.
(a) Set the ENG/MASTER 1 (3KC) switch (panel 115VU) to OFF, and immediately observe the ENG 1 LP fuel valve symbol on the FUEL system page. (b) Make sure the ENG 1 LP fuel valve symbol changes to closed (amber crossline).
(7) If the ENG 1 LP fuel valve:
- transit time from closed to open is 2 seconds (and the transit time from open to closed is 2 seconds), no troubleshooting work steps are necessary
- opens and closes slowly, do Para. 4.A.
NOTE: The above time of 2 seconds is correct for an aircraft with a nominal supply voltage of 28VDC. If the 28VDC supply voltage is low or in ambient conditions of extreme cold the transit time of the actuator will be greater.
NOTE: You can get more data from the:
- Aircraft Maintenance Manual (AMM) AMM 26-12-00-00- AMM 26-21-00-00- AMM 28-24-00-00- and AMM 76-12-00-00-
- Trouble Shooting Manual (TSM) Task Supporting Data
28-24-00-03 TSM TASK 28-24-00-03 - Aircraft Schematic Manual (ASM) ASM 262102 ASM 282401 and ASM 761201.
Subtask 28-24-00-810-058-A
A. Procedure
(3) Examine the C/B-FUEL/LP VALVE/MOT 1/ENG 1 (1QG).
(4) Reset the C/B if found tripped in step (3).
(5) Examine the C/B-FUEL/LP VALVE/MOT 2/ENG 1 (3QG).
(6) Reset the C/B if found tripped in step (5).
(7) Do the test given in Para. 3.A.
(8) If the fault continues:
(a) Disconnect the electrical supply connector 9QG-A from the ACTUATOR-LP FUEL VALVE, ENG 1 (9QG).
1 Make sure the ENG/MASTER 1 (3KC) switch is set to OFF.
2 Using a MULTIMETER - STANDARD do a check to see if 28VDC is available between the pins as shown in the table that follows.
4 Do a check to see if 28VDC is available between the pins as shown in the table that follows.
5 Reconnect the electrical supply connector 9QG-A to the ACTUATOR-LP FUEL VALVE, ENG 1 (9QG).
(b) Disconnect the electrical supply connector 9QG-B from the ACTUATOR-LP FUEL VALVE, ENG 1 (9QG).
1 Do a wiring check AWM 282401 of the aircraft wiring between the ACTUATOR-LP FUEL VALVE, ENG 1 free connector 9QG-B, pin E and the ground point 4003VN(522STA540) to make sure a ground is on pin E of connector 9QG-B.
2 Set the ENG/MASTER 1 (3KC) switch to OFF.
3 Do a check to see if 28VDC is available between the pins as shown in the table that follows.
4 Set the ENG/MASTER 1 (3KC) switch to ON.
5 Do a check to see if 28VDC is available between the pins as shown in the table that follows.
(9) If the supplies are:
(a) Correct as given in the tables above:
1 Replace the ACTUATOR-LP FUEL VALVE, ENG 1 [9QG] , AMM 28-24-51-000-001, and AMM 28-24-51-400-001.
2 If the fault continues:
(11) Do a check to see if 28VDC is available at connector 1WD-B, pin <B AWM 282401.
(12) If the 28VDC supplies are:
(a) Correct as given in the steps (10) and (11):
1 Replace the ENG/APU FIRE PNL [1WD] , AMM 26-12-12-000-001, and AMM 26-12-12-400-001.
2 Do the test given in Para. 3.A.
(b) Not correct as given in step (10):
2 If the fault continues:
4 Do the test given in Para. 3.A.
(c) Not correct as given in step (11):
2 If the fault continues:
4 Do the test given in Para. 3.A.
5. Close-upNOTE: This procedure is for slow transit times in (BOTH) the two directions ONLY.
If the transit time from closed to open is 4 seconds or more, and the transit time from open to closed is 4 seconds or more, this shows that (for a single failure case):
(1) Examine for obvious signs of damage the items that follow: If the transit time from closed to open is 4 seconds or more, and the transit time from open to closed is 4 seconds or more, this shows that (for a single failure case):
- the fault is an item that is common to both the actuator open and close supply lines
- an unserviceable actuator
- an unserviceable valve (partially seized).
- the actuator supply cables and end connectors
- the actuator electrical receptacles
- the cable looms next to the actuator.
NOTE: Left Wing Wire Routing AWM 940502.
(2) Repair (or replace) all the unserviceable wiring and connectors ESPM 2053210. (3) Examine the C/B-FUEL/LP VALVE/MOT 1/ENG 1 (1QG).
(4) Reset the C/B if found tripped in step (3).
(5) Examine the C/B-FUEL/LP VALVE/MOT 2/ENG 1 (3QG).
(6) Reset the C/B if found tripped in step (5).
(7) Do the test given in Para. 3.A.
(8) If the fault continues:
(a) Disconnect the electrical supply connector 9QG-A from the ACTUATOR-LP FUEL VALVE, ENG 1 (9QG).
1 Make sure the ENG/MASTER 1 (3KC) switch is set to OFF.
2 Using a MULTIMETER - STANDARD do a check to see if 28VDC is available between the pins as shown in the table that follows.
| SIGNAL LINE | CONNECTOR 9QG-A |
|---|---|
| MOTOR 1 CLOSE 28VDC SUPPLY | C |
| MOTOR 1 GROUND | E |
NOTE: The correct operation of the LP fuel valve symbol on the FUEL system display page shows that the ground is available on pin E, of connector 9QG-A.
3 Set the ENG/MASTER 1 (3KC) switch to ON. 4 Do a check to see if 28VDC is available between the pins as shown in the table that follows.
| SIGNAL LINE | CONNECTOR 9QG-A |
|---|---|
| MOTOR 1 OPEN 28VDC SUPPLY | A |
| MOTOR 1 GROUND | E |
(b) Disconnect the electrical supply connector 9QG-B from the ACTUATOR-LP FUEL VALVE, ENG 1 (9QG).
1 Do a wiring check AWM 282401 of the aircraft wiring between the ACTUATOR-LP FUEL VALVE, ENG 1 free connector 9QG-B, pin E and the ground point 4003VN(522STA540) to make sure a ground is on pin E of connector 9QG-B.
2 Set the ENG/MASTER 1 (3KC) switch to OFF.
3 Do a check to see if 28VDC is available between the pins as shown in the table that follows.
| SIGNAL LINE | CONNECTOR 9QG-B |
|---|---|
| MOTOR 2 CLOSE 28VDC SUPPLY | C |
| MOTOR 2 GROUND | E |
5 Do a check to see if 28VDC is available between the pins as shown in the table that follows.
| SIGNAL LINE | CONNECTOR 9QG-B |
|---|---|
| MOTOR 2 OPEN 28VDC SUPPLY | A |
| MOTOR 2 GROUND | E |
(a) Correct as given in the tables above:
1 Replace the ACTUATOR-LP FUEL VALVE, ENG 1 [9QG] , AMM 28-24-51-000-001, and AMM 28-24-51-400-001.
2 If the fault continues:
- replace the VALVE-LP FUEL, ENG 1 [12QM] , AMM 28-24-41-000-001, and AMM 28-24-41-400-001.
- remove the ENG/APU FIRE PANEL (1WD) AMM 26-12-12-000-001.
(11) Do a check to see if 28VDC is available at connector 1WD-B, pin <B AWM 282401.
(12) If the 28VDC supplies are:
(a) Correct as given in the steps (10) and (11):
1 Replace the ENG/APU FIRE PNL [1WD] , AMM 26-12-12-000-001, and AMM 26-12-12-400-001.
2 Do the test given in Para. 3.A.
(b) Not correct as given in step (10):
- check/replace C/B-FUEL/LP VALVE/MOT1/ENG1 [1QG] .
2 If the fault continues:
- do a wiring check AWM 282401 of the aircraft wiring between the C/B-FUEL/LP VALVE/MOT 1/ENG 1 (1QG), terminal 2 and the ENG/APU PANEL (1WD) free connector 1WD-A, pin U.
4 Do the test given in Para. 3.A.
(c) Not correct as given in step (11):
- check/replace C/B-FUEL/LP VALVE/MOT2/ENG1 [3QG] .
2 If the fault continues:
- do a wiring check AWM 282401 of the aircraft wiring between the C/B-FUEL/LP VALVE/MOT 2/ENG 1 (3QG), terminal 2 and the ENG/APU PANEL (1WD) free connector 1WD-B, pin <B.
4 Do the test given in Para. 3.A.
Subtask 28-24-00-860-052-A
A. Put the aircraft back to its initial configuration.