W DOC AIRBUS | TSM A320F

Unwanted Activation or Deactivation of the Nose Wheel Steering

TASK 32-51-00-810-833-A
Unwanted Activation or Deactivation of the Nose Wheel Steering

WARNING: BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.
1. Possible Causes
  • ELEC BOX-N/W STEERING,DEACTIVATION [5GC]
  • BSCU [10GG]
  • wiring
  • debris guard
  • DRIVE ASSY-TACHOMETER,WHEEL 1 [2681GM]
  • DRIVE ASSY-TACHOMETER,WHEEL 2 [2680GM]
  • DRIVE ASSY-TACHOMETER,WHEEL 3 [2679GM]
  • DRIVE ASSY-TACHOMETER,WHEEL 4 [2678GM]
  • nose wheel steering servo-valve
  • nosewheel steering servo-valve
  • diode module (2VD)
  • RELAY-N/W STRG DE-ACT [1806GL]
  • C/B-HYDRAULIC/SOL VALVES/G/Y/PTU [1801GL]
2. Job Set-up Information
 A. Consumable Materials
REFERENCE
DESIGNATION
(Material No.03HBD9)
Synthetic Ester base Grease-General Purpose Low Temp -
(Material No.03LBB1)
Grease-Thread Anti-seize Graphited and Petrolatum -
 B. Referenced Information
REFERENCE
DESIGNATION
AMM 05-51-22-200-001
Inspection After a NLG Towing Overload or Overrun
AMM 05-51-23-200-001
Inspection after NLG Steering Angle of more than 95 deg.
AMM 07-11-00-581-003
Lifting of the Aircraft at the Forward Jacking Point, MLG Wheels on the Ground
AMM 07-11-00-586-001
Lowering of the Aircraft at Forward Jacking Point, MLG Wheels on the Ground
AMM 07-12-00-582-001
Jacking of the Nose Landing Gear
AMM 09-10-00-584-002
Towing by the Nose Landing Gear from the Front with a Towbar
AMM 24-41-00-861-002
Energize the Aircraft Electrical Circuits from the External Power
AMM 24-41-00-862-002
De-energize the Aircraft Electrical Circuits Supplied from the External Power
AMM 29-10-00-863-001
Pressurize the Green Hydraulic System with a Hydraulic Ground Power-Cart
AMM 29-10-00-863-002
Pressurize the Yellow Hydraulic System with a Hydraulic Ground Power-Cart
AMM 29-10-00-864-001
Depressurize the Green Hydraulic System
AMM 29-10-00-864-002
Depressurize the Yellow Hydraulic System
ASM 292301
ASM 293101
AMM 31-32-00-860-009
Procedure to Get Access to the SYSTEM REPORT/TEST/L/G Page
ASM 324202
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 32-42-68-000-003
Removal of the MLG Tachometer-Drive
AMM 32-42-68-400-003
Installation of the MLG Tachometer-Drive
ASM 325101
AMM 32-51-12-000-001
Removal of the Nose - Wheel Steering Electrical Deactivation - Box
AMM 32-51-12-400-001
Installation of the Nose - Wheel Steering Electrical Deactivation - Box
AMM 32-51-51-000-002
Removal of the Nose Wheel Steering Servo-Valve
AMM 32-51-51-400-002
Installation of the Nose Wheel Steering Servo-Valve
TSM TASK 32-42-00-03
NORMAL BRAKING - TASK SUPPORTING DATA
F NLG Shock Absorber - Clearance
3. Fault Confirmation
Subtask 32-51-00-210-050-A
A. Visual Inspection
   (1) If the fault occurred during aircraft towing/push-back with the towing lever on the steering deactivation electrical-box 5GC in the normal (engaged) position:
     (a) If you towed/pushed the aircraft without the towbar:
     (b) If you did the standard towing/push-back with the towbar:
  • Do a visual inspection of the wheels, tires and towing lug for damage (because of the towbar).
  • Do the fault isolation procedure.
   (2) If the fault occurred in other conditions:
  • Continue with the test procedure.
Subtask 32-51-00-720-052-A
B. Test
   (1) Do the test of the nose-wheel-steering deactivation electrical-box that follows:
ACTION
RESULT
1.On electrical box 5GC, on the nose gear leg, put the ground towing lever in the TOWING position (disengaged position).
On the upper ECAM DU, on the MEMO page, the NW STRG DISC indication comes into view.
Lock it in this position.
NOTE: If the upper ECAM DU shows a warning, push the CLR key on the ECAM control panel until the MEMO page comes into view on the upper ECAM DU.
2.On the nose gear leg, on electrical box 5GC, put the ground towing lever in the normal position (engaged position).
On the upper ECAM DU, on the MEMO page, the NW STRG DISC indication goes out of view.
   (2) If the test is not correct, go to Para. 4.B
   (3) If the test is correct, go to Para. fault isolation. In this case, troubleshooting can be deferred.
   (4) If the test is correct, but if the fault continues, go to Para. fault isolation.
4. Fault Isolation
Subtask 32-51-00-810-108-A ** ON A/C NOT FOR ALL
A. If the test of the nose-wheel-steering deactivation electrical-box is satisfactory, read the TROUBLE SHOOTING DATA of the BSCU on the MCDU 32-42-00-03 TSM TASK 32-42-00-03.
   (1) If no TROUBLE SHOOTING DATA is available:
  • Do the trouble shooting from step 4.A.(3).(a).
   (2) If the TROUBLE SHOOTING DATA of the BSCU gives the fault code 6F or 810:
     (a) If the fault continues:
       1 If the fault continues:
  • Do a check and repair the wiring between ASM 325101:
    . The BSCU (10GG) pin AB/8D and the nosewheel-steering deactivation electrical-box (5GC) pin A/D
    . The nosewheel-steering deactivation electrical-box (5GC) pin A/C and the ground.
         a If the fault continues:
  • Continue the trouble shooting at step 4.B.(1)(b).
   (3) If the TROUBLE SHOOTING DATA of the BSCU gives the fault code 8E or 8F or 812 or 813:
  • Do a check of the wheel 1, 2, 3 and 4 speed values on the TROUBLE SHOOTING DATA and:
     (a) If the brake fans are not installed:
  • Go to step 4.A.(4)(c).
     (b) If the brake fans are installed:
  • Energize the aircraft electrical circuits AMM 24-41-00-861-002.
  • On the panel 402VU, make sure that the ANTI SKID selector switch is in the ON position.
ACTION
RESULT
1.On the MCDU 1
  • Adjust the brightness of the MCDU screen.
  • Push the MCDU MENU mode key.
On the MCDU 1
  • The MCDU MENU page comes into view.
2.On the MCDU MENU page:
  • Push the line key adjacent to the AIDS indication.
The AIDS page comes into view.
3.Push the line key adjacent to the CALL-UP PARAM indication.
The AIDS PARAM CALL-UP page comes into view.
4.Push the line key adjacent to the PARAM LABEL CALL-UP indication.
The AIDS PAR LAB CALL-UP page comes into view.
5.With the MCDU keyboard, enter the parameter labels as follows:
06E/1/320/01 for wheel 1 speed system 1
06E/2/320/10 for wheel 1 speed system 2

06E/1/321/01 for wheel 2 speed system 1
06E/2/321/10 for wheel 2 speed system 2

06E/1/322/01 for wheel 3 speed system 1
06E/2/322/10 for wheel 3 speed system 2

06E/1/323/01 for wheel 4 speed system 1
06E/2/323/10 for wheel 4 speed system 2
The related parameter label value of the tachometer is 0.
6.On the panel 402VU, push the BRAKE FAN CONTROL pushbutton switch (the ON legend comes on) and monitor the parameter label values.
On the MCDU 1:
  • Push the line key adjacent to the REFRESH indication.
Make sure that the parameter label values of the tachometers are 0 during brake fan spin-up and steady state.
7.On the panel 402VU, release the BRAKE FAN CONTROL pushbutton switch.
On this pushbutton switch, the ON legend goes off. On the four wheels, the fans stop.
Make sure that the parameter label values of the tachometers are 0 during brake fan deceleration.
   (4) If the TROUBLE SHOOTING DATA and/or the test of the tachometers give(s) one or more wheel speed values more than 0 kts:
  • If necessary, apply a thin layer of:
    . the splines of the tachometer drive shaft
    . the debris guard adaptor.
  • Do a check of the tachometer drive assembly of the related wheel and of the related debris guard for damage.
     (a) If you find damage:
     (b) If you do not find damage:
  • If necessary apply a thin layer of Grease-Thread Anti-seize Graphited and Petrolatum - (Material No.03LBB1) to:
    . The splines of the tachometer drive shaft
    . The debris guard adaptor.
  • Do a check and repair the wiring between the BSCU and the related tachometer ASM 324202:
       1 For the wheel 1:
. The BSCU (10GG) pin AB/5K and the tachometer wheel 1 (19GG) pin A/A,
. The BSCU (10GG) pin AB/5J and the tachometer wheel 1 (19GG) pin A/C.
       2 For the wheel 2:
. The BSCU (10GG) pin AB/6K and the tachometer wheel 2 (21GG) pin A/A,
. The BSCU (10GG) pin AB/6J and the tachometer wheel 2 (21GG) pin A/C.
       3 For the wheel 3:
. The BSCU (10GG) pin AB/7K and the tachometer wheel 3 (20GG) pin A/A,
. The BSCU (10GG) pin AB/7J and the tachometer wheel 3 (20GG) pin A/C.
       4 For the wheel 4:
. The BSCU (10GG) pin AB/8K and the tachometer wheel 4 (22GG) pin A/A,
. The BSCU (10GG) pin AB/8J and the tachometer wheel 4 (22GG) pin A/C.
     (c) If the fault continues:
       1 If the fault continues:
         a If the fault continues:
  • Do a check and repair the wiring between ASM 325101:
    . the BSCU (10GG) pin AB/8D and the nosewheel steering deactivation electrical-box (5GC) pin A/D
    . the nosewheel steering deactivation electrical-box (5GC) pin A/C and the ground.
   (5) If the TROUBLE SHOOTING DATA of the BSCU gives the fault code 90 or 814:
  • Do a check of the servovalve
  • Put the aircraft in the necessary configuration to let the nose wheels move freely to the left or the right.
     (a) If it is necessary to do the check with the nose wheels on the ground, do these steps:
NOTE: Two 1.2 m (3.93 ft.) square steel plates are necessary to do this work.
NOTE: The procedure that uses the steel plates cannot be accurate if the friction between the steel plates does not let the nose wheels move freely.
  • Put a steel plate in front of the nose wheels.
  • Apply a thick layer of Synthetic Ester base Grease-General Purpose Low Temp - (Material No.03HBD9) to the upper surface of the steel plate.
  • Put the other steel plate on the top of the greased steel plate.
  • Move the aircraft and put the nose wheels on the greased steel plate AMM 09-10-00-584-002.
  • Continue the trouble shooting at step 4.A.(5)(c).
     (b) If it is necessary to do the check with the nose wheels off the ground, do these steps:
  • Lift the front of the aircraft until the nose wheels are clear off the ground AMM 07-11-00-581-003.
  • Compress the NLG shock absorber with the nosewheel jack until the dimension H
    F NLG Shock Absorber - Clearance ** ON A/C NOT FOR ALL
    is less than 350 mm (13.7795 in.) AMM 07-12-00-582-001.
  • Make sure that there is a sufficient clearance between the jack and the nose wheels to operate the nose wheel steering system.
  • Pressurize the Green hydraulic system AMM 29-10-00-863-001.
     (c) On one MCDU, get the STEERING DATA page for the BSCU SYS 1:
* On the MCDU, get access to the SYSTEM REPORT/TEST/L/G page AMM 31-32-00-860-009.
* On the SYSTEM REPORT/TEST/L/G page, push the line key adjacent to the BSCU1 indication.
* On the BSCU SYS 1 page, push the line key adjacent to the STEERING DATA indication.
* Push the line key adjacent to the REFRESH indication and make sure that the SELV ORDER or STRSELV parameter shows OPEN.
NOTE: If the SELV ORDER or STRSELV parameter shows CLOSE, get the STEERING DATA page for BSCU SYS 2.
* Push the line key adjacent to the REFRESH indication and make sure that the SELV ORDER or STRSELV parameter shows OPEN.
       1 Push and hold the Captain left rudder-pedal fully forward and make sure that the nose wheels move 6 degrees to the left.
       2 Quickly release the rudder-pedal to the neutral position plus or minus 0.5 degrees.
       3 Make sure that the nose wheels move back to the 0 degree position.
       4 When movement of the nose wheels stops, on the MCDU on the STEERING DATA page:
  • Push the line key adjacent to the REFRESH indication.
  • Record the servovalve current SSV CURRENT or ISTRSV parameter (ISV1).
       5 Push and hold the Captain right rudder-pedal fully forward and make sure that the nose wheels move 6 degrees to the right.
       6 Quickly release the rudder-pedal to the neutral position plus or minus 0.5 degrees.
       7 Make sure that the nose wheels move back to the 0 degree position.
       8 When movement of the nose wheels stops, on the MCDU on the STEERING DATA page:
  • Push the line key adjacent to the REFRESH indication.
  • Record the servovalve current SSV CURRENT parameter (ISV2).
       9 Do these checks:
  • Make sure that 0.5 X (ISV1 + ISV2) is less than or equal to plus or minus 0.5 mA.
  • Make sure that (ISV1 - ISV2) is less than or equal to plus or minus 0.5 mA.
         a If the servovalve currents are not correct:
         b If the fault continues:
Subtask 32-51-00-810-108-B ** ON A/C NOT FOR ALL
A. If the test of the nose-wheel-steering deactivation electrical-box is satisfactory, read the TROUBLE SHOOTING DATA (TSD) of the BSCU on the MCDU 32-42-00-03 TSM TASK 32-42-00-03.
   (1) If no TROUBLE SHOOTING DATA is available:
  • Do the trouble shooting from step 4.A.(3).
   (2) If the TROUBLE SHOOTING DATA of the BSCU gives the fault code 6F or 810:
     (a) If the fault continues:
       1 If the fault continues:
  • Do a check and repair the wiring between ASM 325101:
    . The BSCU (10GG) pin AB/8D and the nose-wheel-steering deactivation electrical-box (5GC) pin A/D
    . The nose wheel steering deactivation electrical-box (5GC) pin A/C and the ground.
         a If the fault continues:
  • Continue the trouble shooting at step 4.B.(1)(b).
   (3) If the TROUBLE SHOOTING DATA of the BSCU gives the fault code 8E or 8F or 812 or 813:
  • Do a check of the wheel 1, 2, 3 and 4 speed values on the TROUBLE SHOOTING DATA and:
     (a) If the brake fans are not installed:
  • Go to step 4.A.(4)(c).
     (b) If the brake fans are installed:
  • Energize the aircraft electrical circuits AMM 24-41-00-861-002.
  • On the panel 402VU, make sure that the ANTI SKID selector switch is in the ON position.
ACTION
RESULT
1.On the MCDU 1:
  • Adjust the brightness of the MCDU screen.
  • Push the MCDU MENU mode key.
On the MCDU 1
  • The MCDU MENU page comes into view.
2.On the MCDU MENU page:
  • Push the line key adjacent to the AIDS indication.
The AIDS page comes into view.
3.Push the line key adjacent to the CALL-UP PARAM indication.
The AIDS PARAM CALL-UP page comes into view.
4.Push the line key adjacent to the PARAM LABEL CALL-UP indication.
The AIDS PAR LAB CALL-UP page comes into view.
5.With the MCDU keyboard, enter the parameter labels as follows:
06E/1/320/01 for wheel 1 speed system 1
06E/2/320/10 for wheel 1 speed system 2

06E/1/321/01 for wheel 2 speed system 1
06E/2/321/10 for wheel 2 speed system 2

06E/1/322/01 for wheel 3 speed system 1
06E/2/322/10 for wheel 3 speed system 2

06E/1/323/01 for wheel 4 speed system 1
06E/2/323/10 for wheel 4 speed system 2
The related parameter label value of the tachometer is 0.
6.On the panel 402VU, push the BRAKE FAN CONTROL pushbutton switch (the ON legend comes on) and monitor the parameter label values.
On the MCDU 1:
  • Push the line key adjacent to the REFRESH indication.
Make sure that the parameter label values of the tachometers are 0 during brake fan spin-up and steady state.
7.On the panel 402VU, release the BRAKE FAN CONTROL pushbutton switch.
The ON legend goes off. On the four wheels, the fans stop.
Make sure that the parameter label values of the tachometers are 0 during brake fan deceleration.
   (4) If the TROUBLE SHOOTING DATA and/or the test of the tachometers give(s) one or more wheel speed values more than 0 kts:
  • Do a check of the tachometer drive assembly of the related wheel and of the related debris guard for damage.
     (a) If you find damage:
     (b) If you do not find damage:
  • If necessary, apply a thin layer of Grease-Thread Anti-seize Graphited and Petrolatum - (Material No.03LBB1) to:
    . The splines of the tachometer drive shaft
    . The debris guard adaptor.
  • Do a check and repair the wiring between the BSCU and the related tachometer ASM 324202:
       1 For the wheel 1:
. The BSCU (10GG) pin AB/5K and the tachometer wheel 1 (19GG) pin A/A,
. The BSCU (10GG) pin AB/5J and the tachometer wheel 1 (19GG) pin A/C.
       2 For the wheel 2:
. The BSCU (10GG) pin AB/6K and the tachometer wheel 2 (21GG) pin A/A,
. The BSCU (10GG) pin AB/6J and the tachometer wheel 2 (21GG) pin A/C.
       3 For the wheel 3:
. The BSCU (10GG) pin AB/7K and the tachometer wheel 3 (20GG) pin A/A,
. The BSCU (10GG) pin AB/7J and the tachometer wheel 3 (20GG) pin A/C.
       4 For the wheel 4:
. The BSCU (10GG) pin AB/8K and the tachometer wheel 4 (22GG) pin A/A,
. The BSCU (10GG) pin AB/8J and the tachometer wheel 4 (22GG) pin A/C.
     (c) If the fault continues:
       1 If the fault continues:
         a If the fault continues:
  • Do a check and repair the wiring between ASM 325101:
    . The BSCU (10GG) pin AB/8D and the nosewheel steering deactivation electrical-box (5GC) pin A/D
    . The nosewheel steering deactivation electrical-box (5GC) pin A/C and the ground.
   (5) If the TROUBLE SHOOTING DATA of the BSCU gives the fault code 90 or 814:
  • Do a check of the servovalve
  • Put the aircraft in the necessary configuration to let the nose wheels move freely to the left or the right.
     (a) If it is necessary to do the check with the nose wheels on the ground, do these steps:
NOTE: Two 1.2 m (3.94 ft.) square steel plates are necessary to do this work.
NOTE: The procedure that uses the steel plates cannot be accurate if the friction between the steel plates does not let the nose wheels move freely.
  • Put a steel plate in front of the nose wheels.
  • Apply a thick layer of Synthetic Ester base Grease-General Purpose Low Temp - (Material No.03HBD9) to the upper surface of the steel plate.
  • Put the other steel plate on the top of the greased steel plate.
  • Move the aircraft and put the nose wheels on the greased steel plate AMM 09-10-00-584-002.
  • Continue the trouble shooting at step 4.A.(5)(c).
     (b) If it is necessary to do the check with the nose wheels off the ground, do these steps:
  • Lift the front of the aircraft until the nose wheels are clear off the ground AMM 07-11-00-581-003.
  • Compress the NLG shock absorber with the nosewheel jack until the dimension H
    F NLG Shock Absorber - Clearance ** ON A/C NOT FOR ALL
    is less than 350 mm (13.7795 in.) AMM 07-12-00-582-001.
  • Make sure that there is a sufficient clearance between the jack and the nose wheels to operate the nose wheel steering system.
  • Pressurize the Yellow hydraulic system AMM 29-10-00-863-002.
     (c) On one MCDU, get the STEERING DATA page for the BSCU SYS 1:
* On the MCDU, get access to the SYSTEM REPORT/TEST/L/G page AMM 31-32-00-860-009.
* On the SYSTEM REPORT/TEST/L/G page, push the line key adjacent to the BSCU1 indication.
* On the BSCU SYS 1 page, push the line key adjacent to the STEERING DATA indication.
* Push the line key adjacent to the REFRESH indication and make sure that the SELV ORDER or STRSELV parameter shows OPEN.
NOTE: If the SELV ORDER or STRSELV parameter shows CLOSE, get the STEERING DATA page for BSCU SYS 2.
* Push the line key adjacent to the REFRESH indication and make sure that the SELV ORDER or STRSELV parameter shows OPEN.
       1 Push and hold the Captain left rudder-pedal fully forward and make sure that the nose wheels move 6 degrees to the left.
       2 Quickly release the rudder-pedal to the neutral position plus or minus 0.5 degrees.
       3 Make sure that the nose wheels move back to the 0 degree position.
       4 When movement of the nose wheels stops, on the MCDU on the STEERING DATA page:
  • Push the line key adjacent to the REFRESH indication.
  • Record the servovalve current SSV CURRENT or ISTRSV parameter (ISV1).
       5 Push and hold the Captain right rudder-pedal fully forward and make sure that the nose wheels move 6 degrees to the right.
       6 Quickly release the rudder-pedal to the neutral position plus or minus 0.5 degrees.
       7 Make sure that the nose wheels move back to the 0 degree position.
       8 When movement of the nose wheels stops, on the MCDU on the STEERING DATA page:
  • Push the line key adjacent to the REFRESH indication.
  • Record the servovalve current SSV CURRENT parameter (ISV2).
       9 Do these checks:
  • Make sure that 0.5 X (ISV1 + ISV2) is less than or equal to plus or minus 0.5 mA.
  • Make sure that (ISV1 - ISV2) is less than or equal to plus or minus 0.5 mA.
         a If the servovalve currents are not correct:
         b If the fault continues:
Subtask 32-51-00-810-108-C ** ON A/C NOT FOR ALL
A. If the test of the nose-wheel-steering deactivation electrical-box is satisfactory, read the TROUBLE SHOOTING DATA (TSD) of the BSCU on the MCDU 32-42-00-03 TSM TASK 32-42-00-03.
   (1) If no TROUBLE SHOOTING DATA is available:
  • Do the trouble shooting from step 4.A.(3).
   (2) If the TROUBLE SHOOTING DATA of the BSCU gives the fault code 6F or 810:
     (a) If the fault continues:
       1 If the fault continues:
  • Do a check and repair the wiring between ASM 325101:
    . The BSCU (10GG) pin AB/8D and the nose-wheel-steering deactivation electrical-box (5GC) pin A/D
    . The nose-wheel-steering deactivation electrical-box (5GC) pin A/C and the ground.
         a If the fault continues:
  • Continue the trouble shooting at step 4.B.(1)(b).
   (3) If the TROUBLE SHOOTING DATA of the BSCU gives the fault code 8E or 8F or 812 or 813:
  • Do a check of the wheel 1, 2, 3 and 4 speed values on the TROUBLE SHOOTING DATA and:
     (a) If the brake fans are not installed:
  • Go to step 4.A.(4)(c).
     (b) If the brake fans are installed:
  • Energize the aircraft electrical circuits AMM 24-41-00-861-002.
  • On the panel 402VU, make sure that the ANTI SKID selector switch is in the ON position.
ACTION
RESULT
1.On the MCDU 1:
  • Adjust the brightness of the MCDU screen.
  • Push the MCDU MENU mode key.
On the MCDU 1:
  • The MCDU MENU page comes into view.
2.On the MCDU MENU page:
  • Push the line key adjacent to the AIDS indication.
The AIDS page comes into view.
3.Push the line key adjacent to the CALL-UP PARAM indication.
The AIDS PARAM CALL-UP page comes into view.
4.Push the line key adjacent to the PARAM LABEL CALL-UP indication.
The AIDS PAR LAB CALL-UP page comes into view.
5.With the MCDU keyboard, enter the parameter labels as follows:
06E/1/320/01 for wheel 1 speed system 1
06E/2/320/10 for wheel 1 speed system 2

06E/1/321/01 for wheel 2 speed system 1
06E/2/321/10 for wheel 2 speed system 2

06E/1/322/01 for wheel 3 speed system 1
06E/2/322/10 for wheel 3 speed system 2

06E/1/323/01 for wheel 4 speed system 1
06E/2/323/10 for wheel 4 speed system 2
The related parameter label value of the tachometer is 0.
6.On the panel 402VU, push the BRAKE FAN CONTROL pushbutton switch (the ON legend comes on) and monitor the parameter label values.
On the MCDU 1:
  • Push the line key adjacent to the REFRESH indication.
Make sure that the parameter label values of the tachometers are 0 during brake fan spin-up and steady state.
7.On the panel 402VU, release the BRAKE FAN CONTROL pushbutton switch.
The ON legend goes off. On the four wheels, the fans stop.
Make sure that the parameter label values of the tachometers are 0 during brake fan deceleration.
   (4) If the TROUBLE SHOOTING DATA and/or the test of the tachometers give(s) one or more wheel speed values of more than 0 kts:
  • Do a check of the tachometer drive assembly of the related wheel and of the related debris guard for damage.
     (a) If you find damage:
     (b) If you do not find damage:
  • If necessary, apply a thin layer of Grease-Thread Anti-seize Graphited and Petrolatum - (Material No.03LBB1) to:
    . The splines of the tachometer drive shaft
    . The debris guard adaptor.
  • Do a check and repair the wiring between the BSCU and the related tachometer ASM 324202:
       1 For the wheel 1:
. The BSCU (10GG) pin AB/5K and the tachometer wheel 1 (19GG) pin A/A
. The BSCU (10GG) pin AB/5J and the tachometer wheel 1 (19GG) pin A/C.
       2 For the wheel 2:
. The BSCU (10GG) pin AB/6K and the tachometer wheel 2 (21GG) pin A/A
. The BSCU (10GG) pin AB/6J and the tachometer wheel 2 (21GG) pin A/C.
       3 For the wheel 3:
. The BSCU (10GG) pin AB/7K and the tachometer wheel 3 (20GG) pin A/A
. The BSCU (10GG) pin AB/7J and the tachometer wheel 3 (20GG) pin A/C.
       4 For the wheel 4:
. The BSCU (10GG) pin AB/8K and the tachometer wheel 4 (22GG) pin A/A
. The BSCU (10GG) pin AB/8J and the tachometer wheel 4 (22GG) pin A/C.
     (c) If the fault continues:
       1 If the fault continues:
         a If the fault continues:
  • Do a check and repair the wiring between ASM 325101:
    . The BSCU (10GG) pin AB/8D and the nosewheel-steering deactivation electrical-box (5GC) pin A/D
    . The nosewheel-steering deactivation electrical-box (5GC) pin A/C and the ground.
   (5) If the TROUBLE SHOOTING DATA of the BSCU gives the fault code 90 or 814:
  • Do a check of the servovalve.
  • Put the aircraft in the necessary configuration to let the nosewheels move freely to the left or the right.
     (a) If it is necessary to do the check with the nosewheels on the ground, do these steps:
NOTE: Two 1.2 m (3.94 ft.) square steel plates are necessary to do this work.
NOTE: It is necessary that the friction between the steel plates lets the nosewheels move freely. If not, the trouble shooting that follows cannot be accurate.
  • Put a steel plate in front of the nose wheels.
  • Apply a thick layer of Synthetic Ester base Grease-General Purpose Low Temp - (Material No.03HBD9) to the upper surface of the steel plate.
  • Put the other steel plate on the top of the lubricated steel plate.
  • Move the aircraft and put the nosewheels on the lubricated steel plate AMM 09-10-00-584-002.
  • Continue the trouble shooting at step 4.A.(5)(c).
     (b) If it is necessary to do the check with the nosewheels off the ground, do these steps:
  • Lift the front of the aircraft until the nosewheels are off the ground AMM 07-11-00-581-003.
  • Compress the NLG shock absorber with the nosewheel jack until the dimension H
    F NLG Shock Absorber - Clearance ** ON A/C NOT FOR ALL
    is less than 350 mm (13.7795 in.) AMM 07-12-00-582-001.
  • Make sure that there is a sufficient clearance between the jack and the nosewheels to operate the nosewheel steering system.
  • Pressurize the Green hydraulic system AMM 29-10-00-863-001.
     (c) On one MCDU, get the STEERING DATA page for the BSCU SYS 1:
  • On the MCDU, get access to the SYSTEM REPORT/TEST/L/G page AMM 31-32-00-860-009.
  • On the SYSTEM REPORT/TEST/L/G page, push the line key adjacent to the BSCU1 indication.
  • On the BSCU SYS 1 page, push the line key adjacent to the STEERING DATA indication.
  • Push the line key adjacent to the REFRESH indication and make sure that the SELV ORDER or STRSELV parameter shows OPEN.
    . If the SELV ORDER or STRSELV parameter shows CLOSE, get the STEERING DATA page for BSCU SYS 2.
  • Push the line key adjacent to the REFRESH indication and make sure that the SELV ORDER or STRSELV parameter shows OPEN.
       1 Push and hold the Captain left rudder-pedal fully forward and make sure that the nosewheels move six degrees to the left.
       2 Quickly release the rudder-pedal to the neutral position plus or minus 0.5 degrees.
       3 Make sure that the nosewheels move back to the 0-degree position.
       4 When the movement of the nosewheels stops, on the MCDU on the STEERING DATA page:
  • Push the line key adjacent to the REFRESH indication.
  • Record the servovalve current SSV CURRENT or ISTRSV parameter (ISV1).
       5 Push and hold the Captain right rudder-pedal fully forward and make sure that the nosewheels move six degrees to the right.
       6 Quickly release the rudder-pedal to the neutral position plus or minus 0.5 degrees.
       7 Make sure that the nosewheels move back to the 0-degree position.
       8 When the movement of the nosewheels stops, on the MCDU on the STEERING DATA page:
  • Push the line key adjacent to the REFRESH indication.
  • Record the servovalve current SSV CURRENT parameter (ISV2).
       9 Do these checks:
  • Make sure that 0.5 X (ISV1 + ISV2) is less than or equal to plus or minus 0.5 mA.
  • Make sure that (ISV1 - ISV2) is less than or equal to plus or minus 0.5 mA.
         a If the servovalve currents are not correct:
         b If the fault continues:
Subtask 32-51-00-810-088-A
B. If, during the test of the nose-wheel-steering deactivation electrical-box, on the upper ECAM DU the NW STRG DISC memo indication:
  • stays in view after you put the towing lever in the normal (engaged) position (steering active) or
  • is not shown after you put the lever in the towing (disengaged) position:
    Replace the ELEC BOX-N/W STEERING,DEACTIVATION [5GC] AMM 32-51-12-000-001 and AMM 32-51-12-400-001.
   (1) If the fault continues:
     (a) If the fault continues:
  • Do a check and repair the wiring between ASM 325101:
    . the BSCU (10GG) pin AB/8D and the nosewheel steering deactivation electrical-box (5GC) pin A/D
    . the nosewheel steering deactivation electrical-box (5GC) pin A/C and the ground.
       1 If the fault continues:
  • Continue the trouble shooting at step 4.B.(1)(b).
     (b) If the fault continues:
  • Do a check of the diode module 2VD pins 23 and 8 ASM 292301.
       1 If the diode module 2VD is not OK:
  • Replace the diode module (2VD).
       2 If the diode module 2VD is OK:
  • Do a check for 28VDC at pin A/X1 of the relay 1806GL.
         a If there is no 28VDC:
  • Replace the RELAY-N/W STRG DE-ACT [1806GL] ASM 292301.

    * If the fault continues:
    - Do a check and repair the wiring between ASM 292301:
    . the relay 1806GL pin A/X2 and the diode module 2VD pin 23
    . the diode module 2VD pin 8 and the nosewheel steering deactivation electrical-box (5GC) pin A/D.

         b If there is no 28VDC:
  • Do a check for 28VDC at pin 2 of the circuit breaker 1801GL.

    * If there is no 28VDC:
    - Replace the C/B-HYDRAULIC/SOL VALVES/G/Y/PTU [1801GL] ASM 293101.

    * If there is 28VDC:
    - Do a check and repair the wiring between the circuit breaker 1801GL and the relay 1806GL pin A/X1 ASM 293101.
5. Close-up
Subtask 32-51-00-860-055-A ** ON A/C NOT FOR ALL
A. Put the aircraft back to its initial configuration.
   (1) On the MCDU, push the line key adjacent to the RETURN indication until the CFDS menu page comes into view.
   (2) If necessary, lower the aircraft on its wheels AMM 07-11-00-586-001.
   (3) If the nose wheels are on greased plates, move the aircraft until the nose wheels are off the greased plates. Remove the greased plates AMM 09-10-00-584-002.
   (4) Depressurize the Green hydraulic system
AMM 29-10-00-864-001.
   (5) De-energize the aircraft electrical circuits AMM 24-41-00-862-002.
   (6) Make sure that the work area is clean and clear of tools and other items.
Subtask 32-51-00-860-055-B ** ON A/C NOT FOR ALL
A. Put the aircraft back to its initial configuration.
   (1) On the MCDU, push the line key adjacent to the RETURN indication until the CFDS menu page comes into view.
   (2) If necessary, lower the aircraft on its wheels AMM 07-11-00-586-001.
   (3) If the nose wheels are on greased plates, move the aircraft until the nose wheels are off the greased plates. Remove the greased plates AMM 09-10-00-584-002.
   (4) Depressurize the Yellow hydraulic system
AMM 29-10-00-864-002.
   (5) De-energize the aircraft electrical circuits AMM 24-41-00-862-002.
   (6) Make sure that the work area is clean and clear of tools and other items.
[Rev.8 from Aug 2018] 2026.04.04 04:31:50 UTC
"WTRUIB" 2025