DOC AIRBUS | TSM A320FFuel Filter Blockage and Bypass event
TASK 73-11-00-810-812-A
Fuel Filter Blockage and Bypass event
1. Possible Causes
2. Job Set-up Information
A. Referenced Information
3. Fault Confirmation
Subtask 73-11-00-710-063-A ** ON A/C NOT FOR ALL
Subtask 73-11-00-860-061-A ** ON A/C NOT FOR ALL
[Rev.8 from Aug 2018]
2026.04.04 04:40:43 UTC
Fuel Filter Blockage and Bypass event
1. Possible Causes
2. Job Set-up Information
A. Referenced Information
| REFERENCE | DESIGNATION |
|---|---|
| TSM TASK 71-00-00-810-834-A | General Troubleshooting Guidelines for Additional Troubleshooting Information |
| TSM TASK 71-00-00-810-835-A | Component and Harness Intermittent Troubleshooting Procedure for Guidance Troubleshooting Intermittent Faults |
| TSM TASK 73-34-00-810-806-A | Fuel Filter Delta Pressure Sensor Electrical Failure Channel B |
| TSM TASK 73-34-00-810-807-A | Fuel Filter Delta Pressure Sensor Electrical Failure Channel A |
| AMM 73-11-00-210-804 | General Visual Inspection (GVI) of the Fuel Distribution System |
| AMM 73-11-00-281-801 | Inspection of the Fuel Filter Element for Contamination |
| AMM 73-11-06-000-801 | Removal of the Fuel Filter Element |
| AMM 73-11-06-400-801 | Installation of the Fuel Filter Element |
| AMM 73-21-00-710-807 | Test No.6 - EEC Operation Test (Idle Test) |
| AMM 73-34-21-000-801 | Removal of the Fuel Filter Differential Pressure Sensor |
| AMM 73-34-21-400-801 | Installation of the Fuel Filter Differential Pressure Sensor |
| AMM 78-36-00-010-802 | Opening of the Thrust Reverser Cowl-Doors |
| AMM 78-36-00-410-802 | Closing of the Thrust Reverser Cowl-Doors |
Subtask 73-11-00-710-063-A ** ON A/C NOT FOR ALL
A. Not Applicable
4. Fault IsolationNOTE: The Electronic Engine Control (EEC) has sensed that the pressure drop across the fuel filter differential pressure sensor is large enough to indicate that the fuel filter is clogged and is in bypass. In this condition, the fuel filter will bypass pressurized fuel around the primary filter element into the secondary filter element. The fuel filter is located inside the fuel filter housing on the fuel manifold at the 4 o'clock position.
- Refer to the general troubleshooting guidelines for additional troubleshooting information (Ref. TSM TASK 71-00-00-810-834).
- Refer to the component and harness intermittent troubleshooting procedure for guidance troubleshooting intermittent faults (Ref. TSM TASK 71-00-00-810-835).
WARNING:
BE CAREFUL WHEN YOU DO WORK ON THE ENGINE AFTER SHUTDOWN. THE ENGINE CAN STAY HOT FOR A LONG TIME. IF YOU DO NOT OBEY THIS WARNING, INJURY CAN OCCUR.
WARNING:
REFER TO THE MSDS FOR ALL MATERIAL USED AND THE MANUFACTURER'S SAFETY INSTRUCTIONS FOR ALL EQUIPMENT USED. IF YOU DO NOT OBEY THIS WARNING, INJURY CAN OCCUR.
Subtask 73-11-00-810-061-A ** ON A/C NOT FOR ALL A. Do the steps that follow:
(1) Open the thrust reverser cowl-doors AMM 78-36-00-010-802.
(2) Remove
(3) Inspect the fuel filter for contamination AMM 73-11-00-281-801 and AMM 73-11-00-210-804.
(4) If the fuel filter is contaminated, correct the cause of contamination.
(a) Install a new
(b) Do the test given in Para. 4.B.
(5) If the fault continues:
(a) Do maintenance as needed to remove contamination from the engine fuel system.
(6) If the fuel filter is not contaminated or the fault continues, do a check for faults related to the fuel filter differential pressure sensor (4002KS).
(a) Do a check for maintenance messages regarding an out of range or rate fuel filter differential pressure sensor (4002KS).
1 For maintenance messages on channel A, refer to (Ref. TSM TASK 73-34-00-810-807).
2 For maintenance messages on channel B, refer to (Ref. TSM TASK 73-34-00-810-806).
(b) If fuel filter differential pressure sensor faults are not present, the sensor output may have drifted or failed in range.
1 Replace FUEL FILTER DIFF PRESS SENSOR [4002KS] AMM 73-34-21-000-801 and AMM 73-34-21-400-801.
2 Do the test given in Para. 4.B.
Subtask 73-11-00-710-086-A ** ON A/C NOT FOR ALL 5. Close-up(1) Open the thrust reverser cowl-doors AMM 78-36-00-010-802.
(2) Remove
(3) Inspect the fuel filter for contamination AMM 73-11-00-281-801 and AMM 73-11-00-210-804.
(4) If the fuel filter is contaminated, correct the cause of contamination.
(a) Install a new
(b) Do the test given in Para. 4.B.
(5) If the fault continues:
(a) Do maintenance as needed to remove contamination from the engine fuel system.
(6) If the fuel filter is not contaminated or the fault continues, do a check for faults related to the fuel filter differential pressure sensor (4002KS).
(a) Do a check for maintenance messages regarding an out of range or rate fuel filter differential pressure sensor (4002KS).
1 For maintenance messages on channel A, refer to (Ref. TSM TASK 73-34-00-810-807).
2 For maintenance messages on channel B, refer to (Ref. TSM TASK 73-34-00-810-806).
(b) If fuel filter differential pressure sensor faults are not present, the sensor output may have drifted or failed in range.
1 Replace FUEL FILTER DIFF PRESS SENSOR [4002KS] AMM 73-34-21-000-801 and AMM 73-34-21-400-801.
2 Do the test given in Para. 4.B.
Subtask 73-11-00-860-061-A ** ON A/C NOT FOR ALL
A. Put the aircraft back to its initial configuration.
(1) Make sure that the work area is clean and clear of tools and other items.
(a) Close the thrust reverser cowl-doors AMM 78-36-00-410-802.
(1) Make sure that the work area is clean and clear of tools and other items.
(a) Close the thrust reverser cowl-doors AMM 78-36-00-410-802.