W DOC AIRBUS | TSM A320F

APU Leak Detection

TASK 36-22-00-810-829-A
APU Leak Detection

1. Possible Causes
  • BMC-1 [1HA1]
  • SENSING ELEMENT-OVERHEAT,WING [11HF]
  • wiring
  • OVHT SENS ELEMENT [12HF]
  • OVHT SENS ELEMENT [13HF]
  • OVHT SENS ELEMENT [14HF]
  • OVHT SENS ELEMENT [15HF]
  • OVHT SENS ELEMENT [16HF]
  • OVHT SENS ELEMENT [17HF]
  • OVHT SENS ELEMENT [18HF]
  • OVHT SENS ELEMENT [19HF]
  • CABLE ASSY [20HF]
2. Job Set-up Information
 A. Fixtures, Tools, Test and Support Equipment
REFERENCE
QTY
DESIGNATION
9240SI
1
CONTROLLER-LOOP
 B. Referenced Information
REFERENCE
DESIGNATION
AMM 36-11-00-740-001
BITE Test of the BMC 1(2)
AMM 36-11-34-000-001
Removal of the BMC
AMM 36-11-34-400-001
Installation of the BMC
ASM 362201
AMM 36-22-17-000-001
Removal of the APU Overheat Sensing-Elements
AMM 36-22-17-400-001
Installation of the APU Overheat Sensing-Elements
3. Fault Confirmation
Subtask 36-22-00-710-083-A ** ON A/C NOT FOR ALL
A. Test
   (1) Do the BITE test of the BMC1 AMM 36-11-00-740-001.
4. Fault Isolation
Subtask 36-22-00-810-079-A ** ON A/C NOT FOR ALL
A. If the test gives the maintenance message:
APU LOOP
  • remove the BMC1 (1HA1) AMM 36-11-34-000-001
  • on the shelf 95VU, connect the 9240SI CONTROLLER-LOOP between the connector 1HA1-AA/7B and the ground ASM 362201
  • do a check of the impedance read on the 9240SI CONTROLLER-LOOP.
   (1) If the impedance is more than 10 KOhms:
  • disconnect the 9240SI CONTROLLER-LOOP from the BMC1 connector
  • replace the BMC-1 [1HA1] which is removed AMM 36-11-34-000-001 and AMM 36-11-34-400-001.
  • refer to Para. 4.B.
  • Check the correct installation of sensing element along bleed duct.
  • Perform a wiring check.
   (2) If the impedance is less than 10 KOhms:
  • disconnect the 9240SI CONTROLLER-LOOP from the BMC1 connector
  • do a visual inspection of the sensing elements and cables on the APU loop.
     (a) If a sensing element or cable is damaged:
     (b) If no sensing element is damaged:
  • disconnect the connector between the sensing elements 15HF and 16HF
  • connect the 9240SI CONTROLLER-LOOP between the connector 1HA1-AA/7B and the ground
  • do a check of the impedance read on the 9240SI CONTROLLER-LOOP.
NOTE: You must use a dichotomic method to find the defective sensing element:
  • Disconnect a connector in the middle of a sensing line.
  • Measure the resistance of one of the halves.
    If the measurement is correct, you must do a check of the other half.
    If the measurement is not correct, do the same operation in the defective half again until you find the defective sensing element.
       1 If the impedance is less than 10 KOhms:
  • disconnect the connector between the sensing elements 13HF and 14HF
  • do a check of the impedance read on the 9240SI CONTROLLER-LOOP.
         a If the impedance is less than 10 KOhms:
  • disconnect the connector between the cable 11HF and the sensing element 12HF
  • do a check of the impedance read on the 9240SI CONTROLLER-LOOP.
    . if the impedance is less than 10 KOhms:
    - replace the SENSING ELEMENT-OVERHEAT,WING [11HF] AMM 36-22-17-000-001 and AMM 36-22-17-400-001
    - do a check of the impedance read on the 9240SI CONTROLLER-LOOP
    * if the impedance is less than 10 KOhms:
    - do a check and repair the wiring between the pin AA/7B of the BMC1 (1HA1) and the cable 11HF
    - connect all the cables or connectors disconnected
    - disconnect the 9240SI CONTROLLER-LOOP from the BMC1 connector
    - install the BMC1 (1HA1) AMM 36-11-34-400-001
    - refer to Para. 4.B.
    * if the impedance is more than 10 KOhms:
    - connect all the cables or connectors disconnected
    - disconnect the 9240SI CONTROLLER-LOOP from the BMC1 connector
    - install the BMC1 (1HA1) AMM 36-11-34-400-001
    - refer to Para. 4.B.
    . if the impedance is more than 10 KOhms:
    - disconnect the connector between the sensing elements 12HF and 13HF
    - connect the connector between the cable 11HF and the sensing element 12HF
    - do a check of the impedance read on the 9240SI CONTROLLER-LOOP
    * if the impedance is less than 131 KOhms:
    - replace the OVHT SENS ELEMENT [12HF] AMM 36-22-17-000-001 and AMM 36-22-17-400-001
    - connect all the cables or connectors disconnected
    - disconnect the 9240SI CONTROLLER-LOOP from the BMC1 connector
    - install the BMC1 (1HA1) AMM 36-11-34-400-001
    - refer to Para. 4.B.
    * if the impedance is more than 131 KOhms:
    - replace the OVHT SENS ELEMENT [13HF] AMM 36-22-17-000-001 and AMM 36-22-17-400-001
    - connect all the cables or connectors disconnected
    - disconnect the 9240SI CONTROLLER-LOOP from the BMC1 connector
    - install the BMC1 (1HA1) AMM 36-11-34-400-001
    - refer to Para. 4.B.
         b If the impedance is more than 10 KOhms:
  • connect the connector between the sensing elements 13HF and 14HF
  • disconnect the connector between the sensing elements 14HF and 15HF
  • do a check of the impedance read on the 9240SI CONTROLLER-LOOP.
    . if the impedance is less than 10 KOhms:
    - replace the OVHT SENS ELEMENT [14HF] AMM 36-22-17-000-001 and AMM 36-22-17-400-001
    - connect all the cables or connectors disconnected
    - disconnect the 9240SI CONTROLLER-LOOP from the BMC1 connector
    - install the BMC1 (1HA1) AMM 36-11-34-400-001
    - refer to Para. 4.B.
    . if the impedance is more than 10 KOhms:
    - replace the OVHT SENS ELEMENT [15HF] AMM 36-22-17-000-001 and AMM 36-22-17-400-001
    - connect all the cables or connectors disconnected
    - disconnect the 9240SI CONTROLLER-LOOP from the BMC1 connector
    - install the BMC1 (1HA1) AMM 36-11-34-400-001
    - refer to Para. 4.B.
       2 If the impedance is more than 10 KOhms:
  • connect the connector between the sensing element 15HF and 16HF
  • disconnect the connector between the sensing elements 17HF and 18HF
  • do a check of the impedance read on the 9240SI CONTROLLER-LOOP.
         a If the impedance is less than 10 KOhms:
  • disconnect the connector between the sensing elements 16HF and 17HF
  • do a check of the impedance read on the 9240SI CONTROLLER-LOOP
    * if the impedance is less than 10 KOhms:
    - replace the OVHT SENS ELEMENT [16HF] AMM 36-22-17-000-001 and AMM 36-22-17-400-001
    - connect all the cables or connectors disconnected
    - disconnect the 9240SI CONTROLLER-LOOP from the BMC1 connector
    - install the BMC1 (1HA1) AMM 36-11-34-400-001,
    - refer to Para. 4.B.
    * if the impedance is more than 10 KOhms:
    - replace the OVHT SENS ELEMENT [17HF] AMM 36-22-17-000-001 and AMM 36-22-17-400-001
    - connect all the cables or connectors disconnected
    - disconnect the 9240SI CONTROLLER-LOOP from the BMC1 connector
    - install the BMC1 (1HA1) AMM 36-11-34-400-001
    - refer to Para. 4.B.
         b If the impedance is more than 10 KOhms:
  • connect the connector between the sensing elements 17HF and 18HF
  • disconnect the connector between the sensing element 19HF and the cable 20HF
  • do a check of the impedance read on the 9240SI CONTROLLER-LOOP
    . if the impedance is less than 10 KOhms:
    - disconnect the connector between the sensing elements 18HF and 19HF
    - do a check of the impedance read on the 9240SI CONTROLLER-LOOP.
    * if the impedance is less than 10 KOhms:
    - replace the OVHT SENS ELEMENT [18HF] AMM 36-22-17-000-001 and AMM 36-22-17-400-001
    - connect all the cables or connectors disconnected
    - disconnect the 9240SI CONTROLLER-LOOP from the BMC1 connector
    - install the BMC1 (1HA1) AMM 36-11-34-400-001
    - refer to Para. 4.B.
    * if the impedance is more than 10 KOhms:
    - replace the OVHT SENS ELEMENT [19HF] AMM 36-22-17-000-001 and AMM 36-22-17-400-001
    - connect all the cables or connectors disconnected
    - disconnect the 9240SI CONTROLLER-LOOP from the BMC1 connector
    - install the BMC1 (1HA1) AMM 36-11-34-400-001
    - refer to Para. 4.B.
    . if the impedance is more than 10 KOhms
    - replace the CABLE ASSY [20HF] AMM 36-22-17-000-001 and AMM 36-22-17-400-001
    - connect all the cables or connectors disconnected
    - do a check of the impedance read on the 9240SI CONTROLLER-LOOP
    * if the impedance is less than 10 KOhms:
    - do a check and repair the wiring between the pin AA/8B of the BMC1 (1HA1) and the cable 20HF
    - connect all the cables or connector disconnected
    - disconnect the 9240SI CONTROLLER-LOOP from the BMC1 connector
    - install the BMC1 (1HA1) AMM 36-11-34-400-001
    - refer to Para. 4.B.
    * if the impedance is more than 10 KOhms:
    - disconnect the 9240SI CONTROLLER-LOOP from the BMC1 connector
    - install the BMC1 (1HA1) AMM 36-11-34-400-001
    - refer to Para. 4.B.
Subtask 36-22-00-710-084-A ** ON A/C NOT FOR ALL
B. Do the test given in Para. 3.
[Rev.8 from Aug 2018] 2026.04.04 04:40:30 UTC
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