W DOC AIRBUS | TSM A320F

APU FIRE PUSH Light Fault

TASK 26-22-00-810-802-A
APU FIRE PUSH Light Fault

1. Possible Causes
  • ENG/APU FIRE PNL [1WD]
  • FDU-APU [13WG]
  • wiring
2. Job Set-up Information
 A. Referenced Information
REFERENCE
DESIGNATION
AMM 26-12-12-000-001
Removal of the ENG/APU Fire Panel
AMM 26-12-12-400-001
Installation of the ENG/APU Fire Panel
ASM 261301
AMM 26-13-34-000-001
Removal of the APU Fire-Detection Unit (FDU)
AMM 26-13-34-400-001
Installation of the APU Fire-Detection Unit (FDU)
AMM 26-22-00-710-001
Operational Test of the APU Fire-Extinguishing Loop/Squib
ASM 262202
AMM 33-14-00-710-001
Operational Test of the Lights
3. Fault Confirmation
Subtask 26-22-00-710-051-A
A. The APU FIRE EXTINGUISHING PANEL 20VU (p/n 330TS08Y) has a fault. Special operation is necessary. Incorrect operation causes the APU fire extinguisher bottle to discharge. Airbus supplies a new 20VU panel that corrects this fault. See TFU 26.22.00.007 for more data.
   (1) Maintenance recommendation:
     (a) Before the test:
  • Pull the CIRCUIT BREAKER 30WF on panel 120VU.
     (b) During the test:
  • Push the APU FIRE TEST BUTTON quickly and fully.
  • Hold it fully during the test.
  • Release it quickly.
     (c) After the test:
  • Close the CIRCUIT BREAKER 30WF on panel 120VU.
   (2) Do the operational test of the APU fire-extinguishing system AMM 26-22-00-710-001.
4. Fault Isolation
Subtask 26-22-00-810-064-A
A. If the test gives a different maintenance message:
  • Do the trouble shooting procedure related to the maintenance message.
Subtask 26-22-00-810-062-A
B. If during the test the upper red light row in the APU FIRE PUSH pushbutton switch does not comes on:
   (1) If the test gives a different maintenance message:
  • Do the trouble shooting procedure related to the maintenance message.
   (2) If the fault continues:
     (a) If the fault continues:
     (b) If the fault continues:
  • do a check and repair the wiring if necessary between the:
    FDU (13WG) connector A/E and ANN (5LP) connector A/14,
    ANN (5LP) connector A/15 and CB (1WG),
    ANN (5LP) connector A/13 and PNL (1WD) connector E/B,
    ASM 262202 and ASM 261301
Subtask 26-22-00-810-053-A
C. If during the test the lower red light row in the APU FIRE PUSH pushbutton switch does not comes on:
   (1) If the test gives a different maintenance message:
  • Do the trouble shooting procedure related to the maintenance message.
   (2) If the fault continues:
     (a) If the fault continues:
     (b) If the fault continues:
  • do a check and repair the wiring if necessary between the:
    FDU (13WG) connector B/E and ANN (2LP) connector A/38,
    ANN (2LP) connector A/39 and CB (1WG),
    ANN (2LP) connector A/37 and PNL (1WD) connector F/B,
    ASM 262202 and ASM 261301
Subtask 26-22-00-710-055-A
D. Do the test as given in the Para. 3.A.
5. Close-up
Subtask 26-22-00-860-051-A
A. Put the aircraft back to its initial configuration.
[Rev.8 from Aug 2018] 2026.04.04 04:27:24 UTC
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