W DOC AIRBUS | TSM A320F

Incorrect Activation of the Alternate Braking System

TASK 32-43-00-810-834-A
Incorrect Activation of the Alternate Braking System

1. Possible Causes
  • ABCU [95GG]
  • wiring
  • PRESS XDCR-NORM BRK SPLY [96GG]
  • SEL VALVE-BRK [23GG]
  • BSCU [10GG]
  • XMTR UNIT-ALTN, BRK PEDAL [103GG]
  • PRESS XDCR-BRK, YELLOW L [101GG]
  • PRESS XDCR-BRK, YELLOW R [100GG]
2. Job Set-up Information
 A. Referenced Information
REFERENCE
DESIGNATION
AMM 27-21-00-820-003
Adjustment of the Rudder Mechanical Control
AMM 27-21-00-820-803
Adjustment of the Rods of the Alternate Brake-Pedal Transmitter-Unit
AMM 31-32-00-860-009
Procedure to Get Access to the SYSTEM REPORT/TEST/L/G Page
AMM 31-32-00-869-002
Procedure for the Class 3 Fault Reading
AMM 32-42-00-03-
AMM 32-42-00-710-001
Operational Check of the Normal Braking System
AMM 32-42-11-000-001
Removal of the Brake Selector Valve
AMM 32-42-11-400-001
Installation of the Brake Selector Valve
AMM 32-42-22-000-001
Removal of the Normal-Brake Supply Pressure-Transducer
AMM 32-42-22-400-001
Installation of the Normal-Brake Supply Pressure-Transducer
AMM 32-42-34-000-001
Removal of the Braking/Steering Control Unit (BSCU)
AMM 32-42-34-400-001
Installation of the Braking/Steering Control Unit (BSCU)
AMM 32-43-00-710-002
Operational Check to start the Functional Test of the Alternate Braking Automatically (flight simulated)
ASM 324302
AMM 32-43-34-000-001
Removal of the Alternate Braking Control Unit (ABCU)
AMM 32-43-34-400-001
Installation of the Alternate Braking Control Unit (ABCU)
AMM 32-43-47-000-001
Removal of the Brake-Pedal Transmitter Unit
AMM 32-44-19-000-001
Removal of the Pressure Transducer
AMM 32-44-19-400-001
Installation of the Pressure Transducer
AMM 32-46-00-740-005
BITE Test of BSCU - Normal Braking TEST
F Incorrect Activation of the Alternate Braking System
3. Fault Confirmation
Subtask 32-43-00-740-082-A ** ON A/C NOT FOR ALL
A. Test
   (1) Do a check of the Post Flight Report (PFR) and make sure that the maintenance message ABCU(95GG)/BRK SELECTOR VALVE(23GG) or ABCU(95GG) is shown.
   (2) Make sure that there is no hydraulic leak downstream of the normal brake selector valve (NBSELV) (23GG).
Subtask 32-43-00-730-050-A ** ON A/C NOT FOR ALL
B. Confirmation of the Type of Failure on the TROUBLE SHOOTING DATA page of the BSCU
   (1) Get access to the SYSTEM REPORT/TEST/L/G page AMM 31-32-00-860-009.
ACTION
RESULT
  • Push the line key adjacent to the BSCU1 or BSCU2 indication.
  • The BSCU1 or BSCU2 page comes into view.
  • Push the line key adjacent to the TROUBLE SHOOT DATA indication.
  • The TROUBLE SHOOTING DATA page comes into view.
   (2) If the TSD gives the fault code 2:
     (a) Read the CLASS 3 FAULTS report AMM 31-32-00-869-002:
  • If the TSD gives only the fault code 2, go to Para.4.A.
  • If the TSD gives the fault codes 2 and 15 or 2 and 18:
    * Make sure that, during the same flight, the fault message BRK NORM SELECTOR VALVE TRANSDUCER (96GG) is shown with:
    *- The fault codes 2 and 15, or
    *- The fault codes 2 and 18, or
    *- The fault code 2, and dashes (----) in the NBSELVPT area of the BSCU page 1/2 of the TSD AMM 32-42-00-03-.
    * Go to Para.4.B.
   (3) If the TSD gives the fault code 1600, go to Para.4.C.
   (4) If there is no fault code on the TSD page:
     (a) Do the operational check of the normal braking system with the Captain pedals only AMM 32-42-00-710-001.
       1 Do the BITE test of the normal braking system AMM 32-46-00-740-005.
       2 If the TSD gives only the fault code 2, go to Para.4.A.
       3 If there is no fault code on the TSD page, do the operational check to start the functional test of the alternate braking automatically (flight simulated) AMM 32-43-00-710-002.
       4 Do the BITE test of the normal braking system AMM 32-46-00-740-005.
       5 Read the CLASS 3 FAULTS report AMM 31-32-00-869-002:
  • If the TSD gives only the fault code 1600, go to Para. 4.C.
  • If the TSD gives the fault codes 1600 and 15 or 1600 and 18:
    * Make sure that, during the same flight, the fault message BRK NORM SELECTOR VALVE TRANSDUCER (96GG) is shown with:
    *- The fault codes 1600 and 15, or
    *- The fault codes 1600 and 18, or
    *- The fault code 1600, and dashes (----) in the NBSELVPT area of the BSCU page 1/2 of the TSD AMM 32-42-00-03-.
    * Go to Para.4.B.
4. Fault Isolation
Subtask 32-43-00-810-085-A ** ON A/C NOT FOR ALL
A. If the TSD gives only the fault code 2 AMM 27-21-00-820-003:
   (1) Make sure that there is no distorsion or damage of the rods of the pedal assembly.
   (2) Replace ABCU [95GG] AMM 32-43-34-000-001 and AMM 32-43-34-400-001.
   (3) If the fault continues:
     (a) Do a check and repair the wiring between the two connectors from:
  • The BSCU (10GG) pin AC/9E to the ABCU (95GG) pin A/p ASM 324302
  • The normal-brake supply pressure-transducer (96GG) pins A/D, A/E to the BSCU (10GG) pins AB/7E, AB/7F ASM 324302
  • The normal-brake supply pressure-transducer (96GG) pins A/D, A/E to the ABCU (95GG) pins A/Z, A/AA ASM 324302
  • The ABCU (95GG) power supply pin A/C, A/D to the normal-brake supply pressure-transducer (96GG) pins A/A, A/B ASM 324302.
   (4) If the fault continues:
   (5) If the fault continues:
   (6) If the fault continues:
     (a) Get access to the SYSTEM REPORT/TEST/L/G page AMM 31-32-00-860-009.
ACTION
RESULT
  • Push the line key adjacent to the BSCU1 or BSCU2 indication.
  • The BSCU1 or BSCU2 page comes into view.
  • Push the line key adjacent to the TROUBLE SHOOT DATA (TSD) indication.
  • The TROUBLE SHOOTING DATA page comes into view.
     (b) Record the values of the RIGHT PEDAL UPOT/UREF and LEFT PEDAL UPOT/UREF parameters on the BSCU page 1/2 of the TSD related to the fault code AMM 32-42-00-03-.
NOTE: The RIGHT PEDAL UPOT/UREF value is shown on the left of the BSCU TSD page. The LEFT PEDAL UPOT/UREF value is shown on the right of the BSCU TSD page.
     (c) Record the APTL and APTR pressure values on the BSCU page 2/2 of the TSD related to the fault code 2 AMM 32-42-00-03-.
     (d) Record these values on the operation range graph.
F Incorrect Activation of the Alternate Braking System ** ON A/C NOT FOR ALL
       1 If the recorded values are in area 1 and if the fault continues:
       2 If the recorded values are in area 2:
  • Do a check of the adjustment of the alternate brake pedal transmitter-rods AMM 27-21-00-820-803.
  • Record the values of the RIGHT PEDAL UPOT/UREF and LEFT PEDAL UPOT/UREF parameters on the BSCU page 1/2 of the TSD related to the fault code 2 AMM 32-42-00-03-.
NOTE: The RIGHT PEDAL UPOT/UREF value is shown on the left of the BSCU TSD page. The LEFT PEDAL UPOT/UREF value is shown on the right of the BSCU TSD page.
     (e) Do the test given in Para. 4.D.
Subtask 32-43-00-810-090-A ** ON A/C NOT FOR ALL
B. If the TSD gives:
  • The fault codes 2 and 15, or
  • The fault codes 2 and 18, or
  • The fault code 2, and dashes (-----) in the NBSELVPT area of the BSCU page 1/2 of the TSD AMM 32-42-00-03-, or
  • The fault codes 1600 and 15, or
  • The fault codes 1600 and 18, or
  • The fault code 1600, and dashes (-----) in the NBSELVPT area of the BSCU page 1/2 of the TSD AMM 32-42-00-03-.
   (1) Replace PRESS XDCR-NORM BRK SPLY [96GG] AMM 32-42-22-000-001 and AMM 32-42-22-400-001.
   (2) If the fault continues:
     (a) Do a check and repair the wiring between the two connectors from:
  • The normal-brake supply pressure-transducer (96GG) pins A/D, A/E to the BSCU (10GG) pins AB/7E, AB/7F ASM 324302
  • The normal-brake supply pressure-transducer (96GG) pins A/D, A/E to the ABCU (95GG) pins A/Z, A/AA ASM 324302
  • The ABCU (95GG) power supply pins A/C, A/D to the normal-brake supply pressure-transducer (96GG) pins A/A, A/B ASM 324302.
   (3) If the fault continues:
   (4) Do the test given in Para. 4.D.
Subtask 32-43-00-810-091-A ** ON A/C NOT FOR ALL
C. If the TSD gives only the fault code 1600:
   (1) In the cockpit, put the PARK BRK selector switch to the ON position and make sure that, on the triple pressure indicator (60GG), the pressure values increase on the two sides (RH) and (LH).
   (2) Get access to the TSD related to the fault code 1600:
ACTION
RESULT
  • Push the line key adjacent to the BSCU1 or BSCU2 indication.
  • The BSCU1 or BSCU2 page comes into view.
  • Push the line key adjacent to the TROUBLE SHOOT DATA (TSD) indication.
  • The TROUBLE SHOOTING DATA page comes into view.
   (3) Do a check of the APTL and APTR pressure values on the BSCU page 2/2 of the TSD AMM 32-42-00-03-.
     (a) If the pressure value of the APTL is more than 30 bar (435.1131 psi):
     (b) If the pressure value of the APTR is more than 30 bar (435.1131 psi):
   (4) If the fault continues:
   (5) If the fault continues:
   (6) If the fault continues:
     (a) Do a check and repair the wiring between the two connectors from:
  • The BSCU (10GG) pin AC/9E to the ABCU (95GG) pin A/p ASM 324302
  • The normal-brake supply pressure-transducer (96GG) pins A/D, A/E to the ABCU (95GG) pins A/Z, A/AA ASM 324302.
   (7) If the fault continues:
   (8) Do the test given in Para 4.D.
Subtask 32-43-00-740-086-A ** ON A/C NOT FOR ALL
D. Make sure that no fault is detected:
   (1) Do the operational check of the normal braking system AMM 32-42-00-710-001.
   (2) Do the BITE test of the normal braking system AMM 32-46-00-740-005.
   (3) Make sure that the maintenance message(s) ABCU(95GG)/BRK SELECTOR VALVE(23GG) or ABCU(95GG) is (are) no longer shown.
[Rev.8 from Aug 2018] 2026.04.04 04:31:42 UTC
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