W DOC AIRBUS | TSM A320F

Load-Control Valve (P12) Fault (131-9(A))

TASK 49-00-81-810-861-A
Load-Control Valve (P12) Fault (131-9(A))

1. Possible Causes
  • LOAD CONTROL VALVE SHOWS OPEN SWITCH FAILURE
  • LOAD CONTROL VALVE SHOWS CLOSED SWITCH FAILURE
  • LOAD VALVE SOLENOID SHOWS CIRCUIT FAILURE
  • LOAD VALVE OPEN SIGNAL SHOWS CIRCUIT FAILURE
  • LOAD CONTROL VALVE SHOWS NOT CLOSED
  • LOAD CONTROL VALVE SHOWS OPEN AND CLOSED
  • LOAD CONTROL VALVE SHOWS NOT OPEN
  • damage/contamination of electrical connector P12
  • LOAD CONTROL VLV (8050KM)
  • aircraft wiring
  • ELECTRONIC CONTROL BOX [59KD]
2. Job Set-up Information
 A. Referenced Information
REFERENCE
DESIGNATION
AMM 49-00-00-860-008
APU Start by External Power
AMM 49-51-51-000-004
Removal of the Load Control Valve (131-9(A))
AMM 49-51-51-400-004
Installation of the Load Control Valve (131-9(A))
ASM 496104
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))
3. Fault Confirmation
Subtask 49-00-81-710-072-B ** 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 '>'-key adjacent to the related CFDS failure message.
   (4) If the MCDU menu shows:
LOAD CONTROL VALVE SHOWS OPEN SWITCH FAILURE
or
LOAD CONTROL VALVE SHOWS CLOSED SWITCH FAILURE
or
LOAD VALVE SOLENOID SHOWS CIRCUIT FAILURE
or
LOAD VALVE OPEN SIGNAL SHOWS CIRCUIT FAILURE
  • do the Fault Confirmation that follows:
     (a) Get access to the APU TEST menu.
     (b) Push the TEST line key.
   (5) If the MCDU menu shows
LOAD CONTROL VALVE SHOWS NOT CLOSED
or
LOAD CONTROL VALVE SHOWS OPEN AND CLOSED
  • do the Fault Confirmation that follows:
     (a) Get access to the APU GND SCANNING menu.
   (6) If the MCDU menu shows
LOAD CONTROL VALVE SHOWS NOT OPEN
  • do the Fault Confirmation that follows:
     (a) Start the APU and apply Bleed Air for 20 seconds, minimum AMM 49-00-00-860-008
     (b) Get access to the APU GND SCANNING menu.
4. Fault Isolation
Subtask 49-00-81-810-064-K ** ON A/C NOT FOR ALL
A. If the APU GND SCANNING menu gives the maintenance message:

LOAD CONTROL VALVE (8050KM)

associated with Fault Code Number (FCN) 88, 92, 93, 96, 97 or 127

or

WRG: LOAD VALVE OPEN SIGNAL

associated with Fault Code Number (FCN) 138

  • do a check for damage/contamination of electrical connector P12 of the LOAD CONTROL VALVE (8050KM).
   (1) If the electrical connector P12 is damaged/contaminated:
  • do a repair/cleaning.
   (2) If the electrical connector is OK:
     (a) If the fault continues:
  • do a check and repair of the aircraft wiring from
    the ECB (59KD) AB/F10,D7,D14 to the LOAD CONTROL VALVE (8050KM) P12/1,3,4
    the LOAD CONTROL VALVE (8050KM) P12/2 to GND
    ASM 496104.
       1 If the fault continues:
Subtask 49-00-81-710-073-A ** ON A/C NOT FOR ALL
B. Do the test given in Para. 3.
[Rev.8 from Aug 2018] 2026.04.04 04:40:38 UTC
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