DOC AIRBUS | TSM A320FTroubleshoot the Engine after an Oil Pressure Low or Fluctuating Event
TASK 71-00-00-810-845-A
Troubleshoot the Engine after an Oil Pressure Low or Fluctuating Event
1. Possible Causes
2. Job Set-up Information
A. Referenced Information
3. Fault Confirmation
Subtask 71-00-00-710-102-A ** ON A/C NOT FOR ALL
Subtask 71-00-00-860-057-A ** ON A/C NOT FOR ALL
[Rev.8 from Aug 2018]
2026.04.04 04:35:03 UTC
Troubleshoot the Engine after an Oil Pressure Low or Fluctuating Event
1. Possible Causes
2. Job Set-up Information
A. Referenced Information
| REFERENCE | DESIGNATION |
|---|---|
| TSM TASK 71-00-00-810-846-A | Troubleshoot the Engine after a High Oil Consumption event |
| TSM TASK 79-33-00-810-837-A | Main Oil Pressure Sensor Electrical Failure Channel A |
| TSM TASK 79-33-00-810-838-A | Main Oil Pressure Sensor Electrical Failure Channel B |
| TSM TASK 79-33-00-810-840-A | Main Oil Pressure Sensor Signal Disagreement |
| TSM TASK 79-33-00-810-841-A | Auxiliary Oil Pressure Sensor Electrical Failure |
| AMM 71-00-00-720-811 | Test No. 3 - Idle Power Test |
| AMM 71-00-00-780-802 | Test No. 13 - Main Oil Pressure Test and Adjustment |
| AMM 71-00-00-860-817 | Motor the Engine (Dry Method) |
| AMM 72-00-00-210-811 | Inspection of the Engine after Engine Oil Overtemperature |
| AMM 73-21-00-710-806 | Test No.7 - EEC Operation Test (Self Test) |
| AMM 79-00-00-210-808 | Oil Consumption Monitoring |
| AMM 79-00-00-281-802 | Inspection of the Magnetic Chip Collectors for Oil Contamination |
| AMM 79-00-00-610-801 | Check and Fill the Engine Oil |
| AMM 79-21-01-000-801 | Removal of the Lubrication and Scavenge Oil Pump |
| AMM 79-21-01-400-801 | Installation of the Lubrication and Scavenge Oil Pump |
| AMM 79-33-21-000-801 | Removal of the Main Oil Pressure (MOP) Sensor |
| AMM 79-33-21-400-801 | Installation of the Main Oil Pressure (MOP) Sensor |
Subtask 71-00-00-710-102-A ** ON A/C NOT FOR ALL
A. Investigate the Engine After an Oil Pressure Low or Fluctuating event
(1) Use this troubleshooting procedure to investigate the engine after an oil pressure low or fluctuating event.
(3) Any EEC monitored faults are transmitted to the aircraft Centralized Fault Display Interface Unit (CFDIU). The MCDU allows interactive dialog with the EEC. Use the MCDU to review the previous flight leg fault information, scheduled maintenance fault information and ground fault information. If there are any faults reported troubleshoot them first.
4. Fault Isolation(1) Use this troubleshooting procedure to investigate the engine after an oil pressure low or fluctuating event.
NOTE: The lubrication and scavenge oil pump contains a fixed lubrication trim orifice not an adjustable valve. If there has been a sudden shift of oil pressure the oil pump should be removed and examined prior to further engine operation.
(2) Using the Multipurpose Control and Display Unit (MCDU) test the FADEC system for any recorded faults. Do the EEC system interactive test AMM 73-21-00-710-806. (3) Any EEC monitored faults are transmitted to the aircraft Centralized Fault Display Interface Unit (CFDIU). The MCDU allows interactive dialog with the EEC. Use the MCDU to review the previous flight leg fault information, scheduled maintenance fault information and ground fault information. If there are any faults reported troubleshoot them first.
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 71-00-00-810-110-A ** ON A/C NOT FOR ALL A. Do the steps that follow:
(1) If there is a report of engine oil temperature, refer to AMM 72-00-00-210-811.
(2) If the maintenance messages related to the main oil pressure on channel A appear, refer to (Ref. TSM TASK 79-33-00-810-837).
(3) If the maintenance messages related to the main oil pressure on channel B appear, refer (Ref. TSM TASK 79-33-00-810-838).
(4) If the maintenance messages related to the main oil pressure disagreement appear, refer to (Ref. TSM TASK 79-33-00-810-840).
(5) If the maintenance message related to Auxiliary Oil Pressure (AOP) sensor electrical failure appears, refer to (Ref. TSM TASK 79-33-00-810-841).
(6) If the maintenance message related to Fan Drive Gearbox (FDGS) Auxiliary Pump Failure appears, do a check of the No. 1 and 1.5 bearing compartment chip collector AMM 79-00-00-281-802.
(7) If there are no Electronic Engine Control (EEC) monitored faults reported, make sure that the oil tank has been serviced properly, refer to fill the engine with oil AMM 79-00-00-610-801.
(8) If you must service the oil tank, check the oil consumption rate, refer to oil consumption monitoring AMM 79-00-00-210-808.
(a) If the oil consumption seems excessive, check the engine for leaks, refer to high oil consumption (Ref. TSM TASK 71-00-00-810-846).
(9) If not previously accomplished, do a check of the chip collectors AMM 79-00-00-281-802.
(10) If you do not find any problems, replace SENSOR-PRESSURE, MAIN OIL [4071KS] AMM 79-33-21-000-801 and AMM 79-33-21-400-801.
(a) Prior to running the engine, do an engine dry motor AMM 71-00-00-860-817. During the engine dry motor, look at oil pressure on the lower ECAM display.
1 If oil pressure is more than 0 psi (0 bar) during the engine dry motor, do an engine run to idle to confirm the repair of the fault AMM 71-00-00-720-811.
a If the engine pressure is not OK , go to the next step.
2 If oil pressure during the engine dry motor is 0 psi (0 bar), go to the next step.
(11) If not previously accomplished, replace PUMP-OIL, LUBRICATION AND SCAVENGE [6004EM] AMM 79-21-01-000-801 and AMM 79-21-01-400-801.
(12) Examine the removed lubrification and scavenge oil pump. If damage is found, inspect the engine oil system. Refer to do a laboratory analysis of the engine oil for contamination AMM 79-00-00-281-802.
(a) Disposition of the engine is based on the task criteria.
(13) If not previously accomplished adjust the main oil pressure, refer to do the main oil pressure test and adjustment AMM 71-00-00-780-802.
(a) If the oil pressure cannot be properly maintained and you do not find any problems, remove the engine from service.
5. Close-up(1) If there is a report of engine oil temperature, refer to AMM 72-00-00-210-811.
(2) If the maintenance messages related to the main oil pressure on channel A appear, refer to (Ref. TSM TASK 79-33-00-810-837).
(3) If the maintenance messages related to the main oil pressure on channel B appear, refer (Ref. TSM TASK 79-33-00-810-838).
(4) If the maintenance messages related to the main oil pressure disagreement appear, refer to (Ref. TSM TASK 79-33-00-810-840).
(5) If the maintenance message related to Auxiliary Oil Pressure (AOP) sensor electrical failure appears, refer to (Ref. TSM TASK 79-33-00-810-841).
(6) If the maintenance message related to Fan Drive Gearbox (FDGS) Auxiliary Pump Failure appears, do a check of the No. 1 and 1.5 bearing compartment chip collector AMM 79-00-00-281-802.
(7) If there are no Electronic Engine Control (EEC) monitored faults reported, make sure that the oil tank has been serviced properly, refer to fill the engine with oil AMM 79-00-00-610-801.
(8) If you must service the oil tank, check the oil consumption rate, refer to oil consumption monitoring AMM 79-00-00-210-808.
(a) If the oil consumption seems excessive, check the engine for leaks, refer to high oil consumption (Ref. TSM TASK 71-00-00-810-846).
(9) If not previously accomplished, do a check of the chip collectors AMM 79-00-00-281-802.
(10) If you do not find any problems, replace SENSOR-PRESSURE, MAIN OIL [4071KS] AMM 79-33-21-000-801 and AMM 79-33-21-400-801.
(a) Prior to running the engine, do an engine dry motor AMM 71-00-00-860-817. During the engine dry motor, look at oil pressure on the lower ECAM display.
1 If oil pressure is more than 0 psi (0 bar) during the engine dry motor, do an engine run to idle to confirm the repair of the fault AMM 71-00-00-720-811.
a If the engine pressure is not OK , go to the next step.
2 If oil pressure during the engine dry motor is 0 psi (0 bar), go to the next step.
(11) If not previously accomplished, replace PUMP-OIL, LUBRICATION AND SCAVENGE [6004EM] AMM 79-21-01-000-801 and AMM 79-21-01-400-801.
(12) Examine the removed lubrification and scavenge oil pump. If damage is found, inspect the engine oil system. Refer to do a laboratory analysis of the engine oil for contamination AMM 79-00-00-281-802.
(a) Disposition of the engine is based on the task criteria.
(13) If not previously accomplished adjust the main oil pressure, refer to do the main oil pressure test and adjustment AMM 71-00-00-780-802.
(a) If the oil pressure cannot be properly maintained and you do not find any problems, remove the engine from service.
Subtask 71-00-00-860-057-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.
(1) Make sure that the work area is clean and clear of tools and other items.