W DOC AIRBUS | TSM A320F

Difference of Average Temperature between the L and R Gears

TASK 32-42-00-810-922-A
Difference of Average Temperature between the L and R Gears

1. Possible Causes
  • MONITORING UNIT-BRK TEMP, R [2GW]
  • MONITORING UNIT-BRK TEMP, L [3GW]
  • wiring from the Circuit breaker 1GW to the BTMU(2GW) pin A/A
  • wiring from the BTMU(2GW) to the BSCU(10GG) pin A/B to pin AB/11D
  • wiring from the Circuit breaker 1GW to the BTMU(3GW) pin A/A
  • wiring from the BTMU(3GW) to the BSCU(10GG) pin A/B to pin AB/11C
  • BSCU [10GG]
2. Job Set-up Information
 A. Referenced Information
REFERENCE
DESIGNATION
AMM 32-42-00-870-001
Bleeding of the Normal Braking at the Brake Units
AMM 32-42-27-210-001
Inspection/Check of the Brake with the Wheel Installed
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 32-42-36-860-001
Reactivation of the Normal-Brake Safety-Valve
AMM 32-43-00-870-002
Bleeding of the High Pressure Alternate Braking System
AMM 32-43-16-600-001
Reactivation of the Alternate-Brake Safety-Valve
AMM 32-43-32-600-001
Reactivation of the Alternate-Brake Manifold Safety-Valve
AMM 32-47-00-710-001
Operational Test of the Brake Temperature System
AMM 32-47-00-710-002
Operational Check of Channel 1 (2) of the Brake Temperature Monitoring Unit
ASM 324701
AMM 32-47-18-000-001
Removal of the Brake Temperature Monitoring Unit
AMM 32-47-18-400-001
Installation of the Brake Temperature Monitoring Unit
3. Fault Confirmation
Subtask 32-42-00-710-083-A
A. Test
NOTE: The difference of the average temperature between L and R gears can be caused by external effect(side winds for example). To make sure that it is not the case, it is necessary to let the aircraft return to service (after having done checks as per Para 3.A) and monitor the aircraft at the next operation. But, when there are 3, or more, aircraft log book entries in the last 10 flights, this is an indication that there is a fault in the braking system or in the brake temperature indicating system.Thus the operator must trouble shoot the system as per Para 4.A, to find the cause of the difference of the temperature between L and R main landing gears.
   (1) Do a check of the POST FLIGHT REPORT (PFR) and of entries in the aircraft log book for braking and/or temperature indicating system related problem.
     (a) If there is a temperature indicating and/or braking CFDS maintenance message on the PFR:
  • Refer to the trouble shooting procedure relative to the triggered warning/message and do the applicable trouble shooting.
   (2) Do a check of the last 10 flight entries for a difference of average temperature between the L and R MLG of 392 deg.F (200.00 deg.C) or more in the aircraft log book:
     (a) If there is no entry or less than 3 entries in the log book:
  • Do a check of the clearance between each of the normal and alternate braking pistons (PARK BRK OFF) and their related pressure plate on the related MLG (hot side).
  • Do the inspection/check of the brakes with the wheels installed AMM 32-42-27-210-001.
NOTE: During the inspection/check of the brakes with the wheels installed, make sure that the brake pistons operate correctly.
  • If the inspection/check of the brakes with the wheels installed is OK: Go to Para 3.A.(3).
  • During the inspection/check of the brakes with the wheels installed if the brakes pistons do not operate correctly: Go to Para 4.A.
   (3) Do the operational test of the brake temperature system AMM 32-47-00-710-001.
   (4) Return the aircraft to service and make a record in the aircraft log book to monitor the difference of average temperature between the L and R MLG during the next operation to make sure that the problem is not caused by an external effect.
4. Fault Isolation
Subtask 32-42-00-810-183-A ** ON A/C NOT FOR ALL
A. Procedure
   (1) Do the bleeding of the normal braking at the brakes units AMM 32-42-00-870-001.
NOTE: If there is no pressure at the brake during the bleeding procedure, you must re-activate the related safety valve AMM 32-42-36-860-001.
   (2) Do the bleeding of the high pressure alternate braking system AMM 32-43-00-870-002.
NOTE: If there is no pressure at the brake during the bleeding procedure, you must re-activate the related safety valve AMM 32-43-16-600-001.
   (3) If the fault continues:
  • On each MLG, do the operational check of channel 1(2) of the brake temperature monitoring unit (BTMU) AMM 32-47-00-710-002.
   (4) Following the check of channel 1(2) of the brake temperature monitoring units (BTMU), if output voltages are not correct:
   (5) If the fault continues:
  • Do a check for 28VDC at pin A/A of the BTMU(2GW) ASM 324701.
     (a) if there is no 28VDC:
  • Do a check and repair the wiring from the Circuit breaker 1GW to the BTMU(2GW) pin A/A ASM 324701.
     (b) if there is 28VDC:
  • Do a check and repair the wiring from the BTMU(2GW) to the BSCU(10GG) pin A/B to pin AB/11D ASM 324701.
   (6) If the fault continues:
  • Do a check for 28VDC at pin A/A of the BTMU(3GW) ASM 324701.
     (a) if there is no 28VDC:
  • Do a check and repair the wiring from the Circuit breaker 1GW to the BTMU(3GW) pin A/A ASM 324701.
     (b) if there is 28VDC:
  • Do a check and repair the wiring from the BTMU(3GW) to the BSCU(10GG) pin A/B to pin AB/11C ASM 324701.
   (7) If the fault continues:
Subtask 32-42-00-810-183-B ** ON A/C NOT FOR ALL
A. Procedure
   (1) Do the bleeding of the normal braking at the brakes units AMM 32-42-00-870-001.
NOTE: If there is no pressure at the brake during the bleeding procedure, you must re-activate the related safety valve AMM 32-42-36-860-001.
   (2) Do the bleeding of the high pressure alternate braking system AMM 32-43-00-870-002.
NOTE: If there is no pressure at the brake during the bleeding procedure, you must re-activate the related safety valve AMM 32-43-32-600-001.
   (3) If the fault continues:
  • On each MLG, do the operational check of channel 1(2) of the brake temperature monitoring unit (BTMU) AMM 32-47-00-710-002.
   (4) Following the check of channel 1(2) of the brake temperature monitoring units (BTMU), if output voltages are not correct:
   (5) If the fault continues:
  • Do a check for 28VDC at pin A/A of the BTMU(2GW) ASM 324701.
     (a) if there is no 28VDC:
  • Do a check and repair the wiring from the Circuit breaker 1GW to the BTMU(2GW) pin A/A ASM 324701.
     (b) if there is 28VDC:
  • Do a check and repair the wiring from the BTMU(2GW) to the BSCU(10GG) pin A/B to pin AB/11D ASM 324701.
   (6) If the fault continues:
  • Do a check for 28VDC at pin A/A of the BTMU(3GW) ASM 324701.
     (a) if there is no 28VDC:
  • Do a check and repair the wiring from the Circuit breaker 1GW to the BTMU(3GW) pin A/A ASM 324701.
     (b) if there is 28VDC:
  • Do a check and repair the wiring from the BTMU(3GW) to the BSCU(10GG) pin A/B to pin AB/11C ASM 324701.
   (7) If the fault continues:
Subtask 32-42-00-810-184-A
B. After the subsequent flight make sure that the fault does not continue.
[Rev.8 from Aug 2018] 2026.04.04 04:40:20 UTC
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