W DOC AIRBUS | TSM A320F

AFT Cargo-Compartment Isolation Valve(s) Fault

TASK 21-28-00-810-802-A
AFT Cargo-Compartment Isolation Valve(s) Fault

1. Possible Causes
  • ISOL VALVE AFT CARGO OUTLET [33HN]
  • CARGO VENT CONTROLLER [10HN]
  • wiring
  • ISOL VALVE AFT CARGO INLET [34HN]
  • P/BSW-CARGO SMOKE/TEST [13WH]
  • PUSHBUTTON SWITCH-CARGO VENT/AFT ISOL VALVE (36HN)
  • PUSHBUTTON SWITCH-TEST [16WH]
  • BOARD-ANN LT TEST & INTFC [8LP]
2. Job Set-up Information
 A. Referenced Information
REFERENCE
DESIGNATION
AMM 21-28-00-710-006
Operational Test of the AFT Cargo-Compartment Ventilation-System
ASM 212802
AMM 21-28-34-000-001
Removal of the Ventilation Controller
AMM 21-28-34-400-001
Installation of the Ventilation Controller
AMM 21-28-52-000-001
Removal of the AFT Cargo-Compartment Ventilation Isolation-Valves
AMM 21-28-52-400-001
Installation of the AFT Cargo-Compartment Ventilation Isolation-Valves
AMM 26-17-00-710-001
Operational Test of the Lavatory Smoke-Detection System
AMM 32-69-00-740-001
BITE Check of Landing-Gear Control Interface-Unit (LGCIU) With Use of MCDU to Ensure that Continuous BITE is Operative
3. Fault Confirmation
Subtask 21-28-00-710-051-A
A. Do the operational test of the AFT cargo-compartment ventilation-system AMM 21-28-00-710-006.
NOTE: You must visually monitor the inlet and outlet isolation valves in the AFT cargo compartment during the test.
4. Fault Isolation
Subtask 21-28-00-810-052-A
A. If the isolation valve (33HN) does not operate and the FAULT legend on the pushbutton switch AFT ISOL VALVE, which is installed on the panel 22VU, comes on:
   (1) If the valve is damaged:
   (2) If the fault continues:
   (3) If the fault continues:
  • do a check and repair the wiring between:
    VALVE (33HN) connector A/E and VC (10HN) connector B/X,
    VALVE (33HN) connector A/B and VC (10HN) connector B/Y,
    VALVE (33HN) connector A/A and VC (10HN) connector B/<B,
    VALVE (33HN) connector A/D and VC (10HN) connector B/<A,
    VALVE (33HN) connector A/F and GND,
    VALVE (33HN) connector A/C and GND ASM 212802.
Subtask 21-28-00-810-053-A
B. If the isolation valve (34HN) does not operate and the FAULT legend on the pushbutton switch AFT ISOL VALVE, which is installed on the panel 22VU, comes on:
   (1) If the valve is damaged:
   (2) If the fault continues:
   (3) If the fault continues:
  • do a check and repair the wiring between:
    VALVE (34HN) connector A/E and VC (10HN) connector B/<C,
    VALVE (34HN) connector A/B and VC (10HN) connector B/<D,
    VALVE (34HN) connector A/A and VC (10HN) connector B/<F,
    VALVE (34HN) connector A/D and VC (10HN) connector B/<E,
    VALVE (34HN) connector A/F and GND,
    VALVE (34HN) connector A/C and GND ASM 212802.
Subtask 21-28-00-810-056-A ** ON A/C NOT FOR ALL
C. If the two isolation valves (33HN) and (34HN) do not operate but the FAULT legend on the pushbutton switch AFT ISOL VALVE, which is installed on the panel 22VU, does not come on:
  • do a check for a ground signal at the VC (10HN) connector B/H ASM 212802.
   (1) If there is a ground signal:
  • do a check of the P/BSW-CARGO SMOKE/TEST [13WH] and replace it if necessary ASM 212802.
     (a) If the fault continues:
  • do a check and repair the wiring if necessary between:
    VC (10HN) connector B/H and SW (13WH) connector A/11,
    SW (13WH) connector A12 and GND ASM 212802.
   (2) If the fault continues:
  • do a check for a ground signal at the VC (10HN) connector B/K ASM 212802.
     (a) If there is a ground signal:
       1 If the test gives a different maintenance message, refer to the Fault Symptom List.
     (b) If the fault continues:
  • do a check and repair the wiring if necessary between:
    VC (10HN) connector B/K and SDCU (10WQ) connector A/3C,
    SDCU (10WQ) connector A/3D and GND ASM 212802.
   (3) If the fault continues:
  • do a check for a ground signal at the VC (10HN) connector B/T ASM 212802.
     (a) If there is a ground signal:
  • do a check of the PUSHBUTTON SWITCH-CARGO VENT/AFT ISOL VALVE (36HN) and replace it if necessary ASM 212802.
     (b) If the fault continues:
  • do a check and repair the wiring if necessary between:
    VC (10HN) connector B/T and SW (36HN) connector A/A2,
    SW (36HN) connector A/A3 and GND ASM 212802.
   (4) If the fault continues:
   (5) If the fault continues:
  • do a check and repair the wiring between:
  • VC (10HN) connector B/L and CB (31HN),
  • VC (10HN) connector B/M and GND,
  • VC (10HN) connector B/N and GND,
  • VC (10HN) connector B/Z and GND ASM 212802.
Subtask 21-28-00-810-056-D ** ON A/C NOT FOR ALL
C. If the two isolation valves (33HN) and (34HN) do not operate but the FAULT legend on the pushbutton switch AFT ISOL VALVE, which is installed on the panel 22VU, does not come on:
  • do a check for a ground signal at the VC (10HN) connector B/H ASM 212802.
   (1) If there is a ground signal:
  • do a check of the PUSHBUTTON SWITCH-TEST [16WH] and replace it if necessary ASM 212802.
     (a) If the fault continues:
  • do a check and repair the wiring if necessary between:
    VC (10HN) connector B/H and SW (16WH) connector A/E1,
    SW (16WH) connector A/E3 and GND ASM 212802.
   (2) If the fault continues:
  • do a check for a ground signal at the VC (10HN) connector B/K ASM 212802.
     (a) If there is a ground signal:
       1 If the test gives a different maintenance message, refer to the Fault Symptom List.
     (b) If the fault continues:
  • do a check and repair the wiring if necessary between:
    VC (10HN) connector B/K and SDCU (10WQ) connector A/3C,
    SDCU (10WQ) connector A/3D and GND ASM 212802.
   (3) If the fault continues:
  • do a check for a ground signal at the VC (10HN) connector B/T ASM 212802.
     (a) If there is a ground signal:
  • do a check of the PUSHBUTTON SWITCH-CARGO VENT/AFT ISOL VALVE (36HN) and replace it if necessary ASM 212802.
     (b) If the fault continues:
  • do a check and repair the wiring if necessary between:
    VC (10HN) connector B/T and SW (36HN) connector A/A2,
    SW (36HN) connector A/A3 and GND ASM 212802.
   (4) If the fault continues:
   (5) If the fault continues:
  • do a check and repair the wiring between:
  • VC (10HN) connector B/L and CB (31HN),
  • VC (10HN) connector B/M and GND,
  • VC (10HN) connector B/N and GND,
  • VC (10HN) connector B/Z and GND ASM 212802.
Subtask 21-28-00-810-064-A
D. If the two isolation valves (33HN) and (34HN) operate but the FAULT legend on the pushbutton switch AFT ISOL VALVE, which is installed on the panel 22VU, comes on:
   (1) If the test gives a different maintenance message, refer to the Fault Symptom List.
   (2) If the fault continues:
  • do a check of the BOARD-ANN LT TEST & INTFC [8LP] and replace it if necessary ASM 212802.
   (3) If the fault continues:
   (4) If the fault continues:
  • do a check and repair the wiring between:
    VC (10HN) connector B/S and RELAY (8LP) connector A/14,
    RELAY (8LP) connector A/15 and CB (31HN),
    RELAY (8LP) connector A/13 and SW (36HN) connector A/7,
    RELAY (8LP) connector A/41 and GND ASM 212802.
Subtask 21-28-00-710-060-A
E. Do the test as given in the Para. 3.A.
5. Close-up
Subtask 21-28-00-860-051-A
A. Put the aircraft back to its initial configuration.
[Rev.8 from Aug 2018] 2026.04.04 04:39:08 UTC
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