W DOC AIRBUS | TSM A320F

Loss of Power Supply of the Valves and Fans

TASK 21-26-00-810-802-A
Loss of Power Supply of the Valves and Fans

1. Possible Causes
  • AEVC [10HQ]
  • wiring between the AEVC pin AA/1D and the ground terminal
  • C/B-AIR COND/AVNCS VENT/CTL [6HQ]
  • P/BSW-VENTILATION/BLOWER (13HQ)
  • wiring between the AEVC (10HQ) pin AA/7C and the pushbutton switch (13HQ) pin A D1
  • wiring between the pushbutton switch (13HQ) pin A/D3 and the circuit breaker (5HQ)
  • C/B-AIR COND/AVNCS VENT/CTL [5HQ]
  • wiring between the AEVC pin AA/1B and the circuit breaker (5HQ)
  • P/BSW-VENTILATION/EXTRACT (14HQ)
  • wiring between the AEVC (10HQ) pin AA/2C and the pushbutton switch (14HQ) pin A/D1
  • wiring between the pushbutton switch (14HQ) pin A/D3 and the circuit breaker (6HQ)
  • wiring between the AEVC (10HQ) pin AA/3D and the pushbutton switch (13HQ) pin A/C1
  • wiring between the pushbutton switch (13HQ) pin A/C3 and the pushbutton switch (14HQ) pin A/C2
  • wiring between the AEVC (10HQ) pin AA/3D and the pushbutton switch (14HQ) pin A/C1
  • wiring between the pushbutton switch (14HQ) pin A/C3 and the pushbutton switch (13HL) pin A/C2
  • P/BSW-CABIN PRESS/DITCHING (13HL)
  • wiring between the pushbutton switch (13HL) pin A/C3 and the circuit breaker (6HQ)
2. Job Set-up Information
 A. Referenced Information
REFERENCE
DESIGNATION
TSM TASK 24-00-00-810-803-A
Circuit Breaker Tripped and/or C/B TRIPPED Warning
AMM 21-26-00-710-001
Operational Check of the Avionics Equipment Ventilation-System via MCDU
AMM 21-26-00-710-008
Operational Test to Read the CFDS for CLASS 3 Faults of the AEVC
AMM 21-26-00-710-009
Operational Test to Read the CFDS for LAST LEG REPORT of the AEVC
ASM 212601
ASM 212602
ASM 212603
AMM 21-26-34-000-001
Removal of the Avionics Equipment Ventilation Computer (AEVC)
AMM 21-26-34-400-001
Installation of the Avionics Equipment Ventilation Computer (AEVC)
3. Fault Confirmation
Subtask 21-26-00-865-051-A
A. Table of the circuit breakers used in this procedure:
PANELDESIGNATIONFINLOCATION
** ON A/C ALL
49VUAIR COND/AVNCS VENT/CTL6HQD06
49VUAIR COND/AVNCS VENT/CTL5HQD05
122VUAIR COND/AVNCS/VENT/MONG3HQY17
Subtask 21-26-00-710-052-A
B. Test
   (1) Do the reset of the AEVC (10HQ).
     (a) Open the circuit breaker AIR COND/AVNCS/VENT/MONG (3HQ).
     (b) Wait for five seconds.
     (c) Close the circuit breaker AIR COND/AVNCS/VENT/MONG (3HQ).
   (2) Do the operational test of the avionics equipment ventilation from the Multipurpose Control and Display Unit (MCDU) AMM 21-26-00-710-001.
   (3) Read the LAST LEG REPORT of the AEVC AMM 21-26-00-710-009.
   (4) Read the CLASS 3 faults of the AEVC AMM 21-26-00-710-008.
4. Fault Isolation
Subtask 21-26-00-810-051-A
A. If the test gives the maintenance message CHECK AEVC SUPPLY:
  • do a check of the status of the circuit breaker (5HQ).
   (1) If the circuit breaker (5HQ) is closed:
     (a) If there is 28VDC at the pins AA/7C and/or AA/1B:
  • do a check of the status of the circuit breaker (6HQ).
       1 If the circuit breaker (6HQ) is closed:
  • do a check for 28VDC at pin AA/1C of the AEVC (10HQ) ASM 212603.
         a If there is 28VDC:
  • do a check for a ground signal at pin AA/1D of the AEVC (10HQ) ASM 212601.

    . If there is a ground signal:
    * replace the AEVC [10HQ] AMM 21-26-34-000-001 and AMM 21-26-34-400-001.

    . If there is no ground signal:
    * repair the wiring between the AEVC pin AA/1D and the ground terminal.
         b If there is no 28VDC:
  • do a check of the wiring between the AEVC pin AA/1C and the circuit breaker (6HQ) ASM 212603.

    . If there is no continuity:
    * repair the related wiring.

    . If there is continuity:
    * replace the circuit breaker C/B-AIR COND/AVNCS VENT/CTL [6HQ] .

    . If the fault continues:
    * replace the AEVC [10HQ] AMM 21-26-34-000-001 and AMM 21-26-34-400-001.
       2 If the circuit breaker (6HQ) is open:
         a If the fault continues:
  • replace the C/B-AIR COND/AVNCS VENT/CTL [6HQ] .
         b If the fault continues:
     (b) If there is no 28VDC at pin AA/7C:
  • do a check for 28VDC at pin A/D3 of the VENTILATION/BLOWER pushbutton switch (13HQ) ASM 212603.
       1 If there is 28VDC:
  • replace the P/BSW-VENTILATION/BLOWER (13HQ).
       2 If there is no 28VDC:
  • do a check of the wiring between the AEVC (10HQ) pin AA/7C and the pushbutton switch (13HQ) pin A D1 and wiring between the pushbutton switch (13HQ) pin A/D3 and the circuit breaker (5HQ).
         a If there is no continuity:
  • repair the related wiring.
         b If there is continuity:
     (c) If there is no 28VDC at pin AA/1B:
  • do a check of the wiring between the AEVC pin AA/1B and the circuit breaker (5HQ).
       1 If there is no continuity:
  • repair the related wiring.
       2 If there is continuity:
         a If the fault continues:
  • replace the circuit breaker C/B-AIR COND/AVNCS VENT/CTL [5HQ] .
   (2) If the circuit breaker (5HQ) is open:
     (a) If the fault continues:
  • replace the C/B-AIR COND/AVNCS VENT/CTL [5HQ] .
     (b) If the fault continues:
   (3) Do a check of the status of the circuit breaker (6HQ).
     (a) If the circuit breaker (6HQ) is closed:
  • do a check for 28VDC at pin AA/2C and/or pin AA/3D of the AEVC (10HQ) ASM 212602.
       1 If there is 28VDC at pins AA/2C and/or AA/3D:
  • do a check for 28VDC at pin AA/1C of the AEVC (10HQ) ASM 212603.
         a If there is 28VDC:
  • do a check for a ground signal at pin AA/1D of the AEVC (10HQ) ASM 212603.

    . If there is a ground signal:
    * replace the AEVC [10HQ] AMM 21-26-34-000-001 and AMM 21-26-34-400-001.

    . If there is no ground signal:
    * repair the wiring between the AEVC pin AA/1D and the ground terminal.
         b If there is no 28VDC:
  • do a check of the wiring between the AEVC pin AA/1C and the circuit breaker (6HQ) ASM 212603.

    . If there is no continuity:
    * repair the related wiring.

    . If there is continuity:
    * replace the circuit breaker C/B-AIR COND/AVNCS VENT/CTL [6HQ] .

    . If the fault continues:
    * replace the AEVC [10HQ] AMM 21-26-34-000-001 and AMM 21-26-34-400-001.
       2 If there is no 28VDC at pin AA/2C:
  • do a check for 28VDC at pin A/D3 of the VENTILATION/EXTRACT pushbutton switch (14HQ) ASM 212602.
         a If there is 28VDC:
  • replace the P/BSW-VENTILATION/EXTRACT (14HQ).
         b If there is no 28VDC:
  • do a check of the wiring between the AEVC (10HQ) pin AA/2C and the pushbutton switch (14HQ) pin A/D1 and wiring between the pushbutton switch (14HQ) pin A/D3 and the circuit breaker (6HQ).
    . If there is no continuity:
    * repair the related wiring.
    . If there is continuity:
    * replace the AEVC [10HQ] AMM 21-26-34-000-001 and AMM 21-26-34-400-001.

    . If the fault continues:
    * replace the circuit breaker C/B-AIR COND/AVNCS VENT/CTL [6HQ] .
       3 If there is no 28VDC at pin AA/3D:
  • do a check for 28VDC at pin A/C3 of the VENTILATION/BLOWER pushbutton switch (13HQ) ASM 212602.
         a If there is 28VDC:
  • replace the P/BSW-VENTILATION/BLOWER (13HQ).
         b If there is no 28VDC:
  • do a check of the wiring between the AEVC (10HQ) pin AA/3D and the pushbutton switch (13HQ) pin A/C1 and wiring between the pushbutton switch (13HQ) pin A/C3 and the pushbutton switch (14HQ) pin A/C2 and wiring between the AEVC (10HQ) pin AA/3D and the pushbutton switch (14HQ) pin A/C1.
    . If there is no continuity:
    * repair the related wiring.
    . If there is continuity:
    * do a check for 28VDC at pin A/C3 of the VENTILATION/EXTRACT pushbutton switch (14HQ) ASM 212602.
    If there is 28VDC:
    replace the P/BSW-VENTILATION/EXTRACT (14HQ).
    If there is no 28VDC:
    ** do a check of the wiring between the pushbutton switch (14HQ) pin A/C3 and the pushbutton switch (13HL) pin A/C2.
    If there is no continuity:
    repair the related wiring.
    If there is continuity:
    *** do a check for 28VDC at pin A/C3 of the CABIN PRESS/DITCHING pushbutton switch (13HL) ASM 212602.
    If there is 28VDC:
    replace the P/BSW-CABIN PRESS/DITCHING (13HL).
    If there is no 28VDC:
    **** do a check of the wiring between the pushbutton switch (13HL) pin A/C3 and the circuit breaker (6HQ).
    If there is no continuity:
    repair the related wiring.
    If there is continuity:
    replace the AEVC [10HQ] AMM 21-26-34-000-001 and AMM 21-26-34-400-001.
    ***** If the fault continues:
    replace the C/B-AIR COND/AVNCS VENT/CTL [6HQ] .
     (b) If the circuit breaker (6HQ) is open:
       1 If the fault continues:
replace the C/B-AIR COND/AVNCS VENT/CTL [6HQ] .
       2 If the fault continues:
Subtask 21-26-00-710-053-A
B. Do the operational test given in Para. 3.
[Rev.8 from Aug 2018] 2026.04.04 04:24:36 UTC
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