W DOC AIRBUS | TSM A320F

False ELAC Warning due to Faulty Hydraulic Pressure Switch

TASK 27-93-00-810-947-A
False ELAC Warning due to Faulty Hydraulic Pressure Switch

1. Possible Causes
2. Job Set-up Information
 A. Referenced Information
REFERENCE
DESIGNATION
AMM 27-96-00-740-001
BITE Test of the EFCS (Ground Scanning)
AMM 29-10-00-200-008
Check Nitrogen Charge Pressure on Hydraulic Power Accumulators
AMM 29-10-00-863-003
Pressurize the Blue Hydraulic System with a Hydraulic Ground Power-Cart
AMM 29-10-00-864-003
Depressurize the Blue Hydraulic System
AMM 29-23-00-863-001
Pressurize the Green Hydraulic System from the Yellow Hydraulic System through the PTU with the Electric Pump
AMM 29-23-00-864-001
Depressurize the Green and Yellow Hydraulic Systems after Operation of the PTU
AMM 29-24-00-863-001
Pressurize the Yellow Hydraulic System with the Electric Pump
AMM 29-24-00-864-001
Depressurize the Yellow Hydraulic System
ASM 293201
AMM 29-32-12-000-003
Removal of the System Pressure Switch
AMM 29-32-12-400-003
Installation of the System Pressure Switch
AMM 31-53-34-000-001
Removal of the Flight Warning Computer (FWC)
AMM 31-53-34-400-001
Installation of the Flight Warning Computer (FWC)
3. Fault Confirmation
Subtask 27-93-00-860-084-A
A. Job Set-Up
   (1) Pressurize the aircraft hydraulic systems AMM 29-10-00-863-003, AMM 29-23-00-863-001 and AMM 29-24-00-863-001.
   (2) On the center pedestal, on the ECAM control panel:
Push the F/CTL key, the F/CTL page comes into view.
   (3) For the ELAC1, on the overhead panel 24VU, release the FLT CTL/ELAC2 pushbutton switch (on this pushbutton switch, the OFF legend comes on).
   (4) For the ELAC2, on the overhead panel 23VU, release the FLT CTL/ELAC1 pushbutton switch (on this pushbutton switch, the OFF legend comes on).
Subtask 27-93-00-810-222-A
B. Put the aircraft back to its initial configuration.
   (1) Depressurize the aircraft hydraulic systems AMM 29-10-00-864-003, AMM 29-23-00-864-001 and AMM 29-24-00-864-001.
   (2) Push the FLT CTL/ELAC1 pushbutton switch or FLT CTL/ELAC2 pushbutton switch that you released before (on this pushbutton switch, the OFF legend goes off).
4. Fault Isolation
Subtask 27-93-00-810-223-A
A. If the ELAC 1 FAULT warning goes out view when the hydraulic systems are pressurized:
   (1) If the BITE test gives a maintenance message related to the hydraulic pressure switch with a F/CTL maintenance status:
  • Do the trouble shooting procedure related to this maintenance message.
   (2) If the BITE test does not give a maintenance message:
     (a) If the fault continues:
     (b) If the fault continues:
     (c) If the fault continues:
     (d) If the fault continues:
  • Do a check and repair the wiring from the FWC 1 to the SYSTEM-PRESS-SW [1151GN] ASM 293201.
     (e) If the fault continues:
  • Do a check and repair the wiring from the FWC 1 to the SYSTEM-PRESS-SW [2151GN] ASM 293201.
Subtask 27-93-00-810-247-A
B. If the ELAC 2 FAULT warning goes out view when the hydraulic systems are pressurized:
   (1) If the BITE test gives a maintenance message related to the hydraulic pressure switch with a F/CTL maintenance status:
  • Do the trouble shooting procedure related to this maintenance message.
   (2) If the BITE test does not give a maintenance message:
     (a) If the fault continues:
     (b) If the fault continues:
     (c) If the fault continues:
     (d) If the fault continues:
     (e) If the fault continues:
  • Do a check and repair the wiring from the FWC 1 to the SYSTEM-PRESS-SW [1151GN] ASM 293201.
     (f) If the fault continues:
  • Do a check and repair the wiring from the FWC 1 to the SYSTEM-PRESS-SW [2151GN] ASM 293201.
     (g) If the fault continues:
  • Do a check and repair the wiring from the FWC 1 to the SYSTEM-PRESS-SW [3151GN] ASM 293201.
Subtask 27-93-00-710-062-A
C. Do the test given in Para. 3.
[Rev.8 from Aug 2018] 2026.04.04 04:39:10 UTC
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