W DOC AIRBUS | TSM A320F

Lube Pump Filter SW P9/GEN SCAV Filter SW P5 Fault (131-9(A))

TASK 49-90-00-810-812-A
Lube Pump Filter SW P9/GEN SCAV Filter SW P5 Fault (131-9(A))

1. Possible Causes
  • OIL FILTER SWITCH SHOWS ELECTRICAL GROUND
  • damage/contamination of the electrical connector P9 and P5
2. Job Set-up Information
 A. Referenced Information
REFERENCE
DESIGNATION
AMM 49-00-00-860-008
APU Start by External Power
AMM 49-00-00-860-009
APU Shutdown by External Power (131-9(A))
AMM 49-11-11-000-004
Removal of the Power Plant (APU) (131-9(A))
AMM 49-11-11-400-004
Installation of the Power Plant (APU) (131-9(A))
AMM 49-61-34-000-003
Removal of the Electronic Control Box (ECB) (131-9(A))
AMM 49-61-34-400-003
Installation of the Electronic Control Box (ECB) (131-9(A))
AMM 49-91-14-000-002
Removal of the Oil Filter Differential Pressure Switches (131-9(A))
AMM 49-91-14-400-002
Installation of the Oil Filter Differential Pressure Switches (131-9(A))
3. Fault Confirmation
Subtask 49-90-00-710-062-A ** ON A/C NOT FOR ALL
A. Read-out of ECB Trouble Shooting Data
   (1) Put the APU MASTER SW to the ON position.
   (2) Get access to the APU LAST LEG/PREVIOUS LEG report.
   (3) Push the '>' adjacent to the related CFDS failure message:
  • the MCDU menu shows:
    OIL FILTER SWITCH SHOWS ELECTRICAL GROUND

  • do the Fault Confirmation that follows:
     (a) Start the APU AMM 49-00-00-860-008.
     (b) Get access to the APU GND SCANNING menu.
     (c) Shut down the APU AMM 49-00-00-860-009.
     (d) Wait until the ECB (59KD) power-down, speed < 7% plus 30 seconds.
     (e) Get access to the APU GND SCANNING menu.
4. Fault Isolation
Subtask 49-90-00-810-056-A ** ON A/C NOT FOR ALL
A. If the APU GND SCANNING menu gives the maintenance message:

LUBE PUMP FILTER SW P9 / GEN SCAV FILTER SW P5

associated with Fault Code Number (FCN) 101

  • do a check for damage/contamination of the electrical connector P9 and P5 of the LUBE PUMP FILTER / GENERATOR SCAV FILTER.
   (1) If the electrical connector P9 and/or P5 is damaged, do a repair. If it is
  • contaminated, clean it.
   (2) If the electrical connector are servicable.
     (a) Remove the connectors P5 and P9 on the APU.
     (b) With the APU off, do a test of the continuity across pins 1+2 at the filter DP switches, value should be >10 kOhm.
     (c) With the APU off, test the continuity from pin 1 and switch case at the filter DP switches, value should be >10 kOhm.
     (d) If either switch do not pass the above checks, replace it. This can be the solution of the problem.
  • If the switches pass the check, continue.
     (e) The oil temperature should be < 80[F, then start the APU and monitor the DP switches with a multi-meter while the oil temperature increase.
  • Monitor if either switch closes during or after the start ( a closed switch is specified as < 30 Ohm ).
     (f) Monitor APU Toil until the temperature is more than 100[F (38[C). You can apply an electrical load to the APU to increase the APU oil temperature faster.
  • APU Toil can be given through the ECAM by the aircraft AIDS system, code "OTA".
  • After the APU oil temperature has increased to over 38[C, do a test if both DP switches are open.
   (3) If no problems were found with the above procedure, do a test of the APU wiring harness as follows.
  • Install connector P5 and P9.
  • Remove connector P1 at the APU compartment bulkhead.
  • Do a test of the continuity across pins 4+9 at the firewall, no continuity is permitted.
  • Do a test of the continuity across pin 9 and structural ground, no continuity is permitted.
  • Bend the wires near the plugs to test for intermittent short circuits.
   (4) If no problems were found with the above procedure, do a test of the aircraft wiring harness as follows.
  • Install connector P1 at the APU compartment bulkhead.
  • Remove the ECB.
  • Do a test of the continuity from pin C11 to structural ground, no continuity is permitted.
  • Bend the wires near the plugs to test for intermittent short-circuits.
   (5) If no problems were found with the above procedure, replace both DP switches AMM 49-91-14-000-002 and AMM 49-91-14-400-002.
   (6) If the fault continues:
   (7) If the fault continues:
Subtask 49-90-00-810-056-B ** ON A/C NOT FOR ALL
A. If the APU GND SCANNING menu gives the maintenance message:

OIL FILTER SWITCHES (8070KM)/(8071KM)

associated with Fault Code Number (FCN) 101

  • do a check for damage/contamination of the electrical connector P9 and P5 of the OIL FILTER SWITCHES (8070KM)/(8071KM)
   (1) If the electrical connector P9 and/or P5 is damaged do a repair. If it is
  • contaminated, clean it.
   (2) If the electrical connector are servicable:
     (a) Remove the connectors P5 and P9 on the APU.
     (b) With the APU off, do a test of the continuity across pins 1+2 at the filter DP switches, value should be >10 kOhm.
     (c) With the APU off, do a testof the continuity from pin 1 and switch case at the filter DP switches, value should be >10 kOhm.
     (d) If either switch do not pass the above test, replace it. This can be the solution of the problem.
  • If the switches pass the test, continue.
     (e) The oil temperature should be < 80[F, then start the APU and monitor both DP switches with a multi-meter while the oil temperature increase.
  • Monitor if either switch closes during or after the the start ( a closed switch is specified as < 30 Ohm ).
     (f) Monitor APU Toil until the temperature is more than 100[F (38[C). You can apply an electrical load to the APU to increase the APU oil temperature faster.
  • APU Toil can be given through the ECAM by the aircraft AIDS system, code "OTA".
  • After the APU oil temperature has increased to over 38[C, do a check if both DP switches are open.
   (3) If no problems were found with the above procedure, test the APU wiring harness as follows.
  • Install connector P5 and P9.
  • Remove connector P1 at the APU compartment bulkhead.
  • Test the continuity across pins 4+9 at the firewall, no continuity is permitted.
  • Test the continuity across pin 9 and structural ground, no continuit is permitted.
  • Bend the wires near the plugs to test for intermittent short-circuits.
   (4) If no problems were found with the above procedure, test the aircraft wiring harness as follows.
  • Install connector P1 at the APU compartment bulkhead.
  • Remove the ECB.
  • Test continuity from pin C11 to structural ground, no continuity is permitted.
  • Bend the wires near the plugs to test for intermittent short-circuits.
   (5) If no problems were found per the above procedure, replace both DP switches AMM 49-91-14-000-002 and AMM 49-91-14-400-002.
   (6) If the fault continues:
   (7) If the fault continues:
Subtask 49-90-00-710-063-A ** ON A/C NOT FOR ALL
B. Do the test given in Para. 3.
[Rev.8 from Aug 2018] 2026.04.04 04:34:42 UTC
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