W DOC AIRBUS | TSM A320F

Upstream NAI Valve Failed Open with the NAI Pushbutton Switch Released on Channels A and B

TASK 30-21-00-810-822-A
Upstream NAI Valve Failed Open with the NAI Pushbutton Switch Released on Channels A and B

1. Possible Causes
  • NAI SOLENOID BLOCK [4190KS]
  • NACELLE ANTI-ICE UPPER VALVE AND ATTACHMENT HARDWARE [4010DN]
  • W04 HARNESS [4088KS]
  • W03 HARNESS [4087KS]
  • PRESS XDCR-ENGINE AIR INTAKE ANTI ICE, 2 [4003DN]
  • [4000KS]
2. Job Set-up Information
 A. Fixtures, Tools, Test and Support Equipment
REFERENCE
QTY
DESIGNATION
No specific
1
PLIERS - JAWED, SOFT
 B. Referenced Information
REFERENCE
DESIGNATION
TSM TASK 71-00-00-810-835-A
Component and Harness Intermittent Troubleshooting Procedure for Guidance Troubleshooting Intermittent Faults
AMM 30-21-00-710-002
Operational Test of the Engine Air Intake Ice Protection (with the Engines in operation)
AMM 30-21-21-000-801
Removal of the Nacelle Anti-Ice Solenoid-Manifold
AMM 30-21-21-400-801
Installation of the Nacelle Anti-Ice Solenoid-Manifold
AMM 30-21-23-000-801
Removal of the Nacelle Anti-Ice Fan-Pressure-Transducer
AMM 30-21-23-400-801
Installation of the Nacelle Anti-Ice Fan-Pressure-Transducer
AMM 30-21-51-000-802
Removal of the Upper Anti-Ice Valve
AMM 30-21-51-400-802
Installation of the Upper Anti-Ice Valve
AMM 31-32-00-860-012
Procedure to Get Access to the SYSTEM REPORT/TEST/ENG Page
AWM 715134
AMM 73-21-01-000-801
Removal of the Electronic Engine Control (EEC)
AMM 73-21-01-400-801
Installation of the Electronic Engine Control (EEC)
AMM 73-21-63-000-802
Removal of the Electronic Engine Control (EEC) Wiring Harness (W03)
AMM 73-21-63-400-802
Installation of the Electronic Engine Control (EEC) Wiring Harness (W03)
AMM 73-21-64-000-802
Removal of the Electronic Engine Control (EEC) Wiring Harness (W04)
AMM 73-21-64-400-802
Installation of the Electronic Engine Control (EEC) Wiring Harness (W04)
AMM 78-36-00-010-802
Opening of the Thrust Reverser Cowl-Doors
AMM 78-36-00-410-802
Closing of the Thrust Reverser Cowl-Doors
3. Fault Confirmation
Subtask 30-21-00-730-059-A ** ON A/C NOT FOR ALL
A. Test
   (1) Do the operational test of the engine air-intake ice-protection AMM 30-21-00-710-002.
   (2) On the MCDU screen, get access to the SYSTEM REPORT/TEST/ENG menu page AMM 31-32-00-860-012.
     (a) On the SYSTEM REPORT/TEST/ENG menu page, push the line key adjacent to the FADEC 1(2) A(B) indication.
The EEC 1(2) CHAN A(B) page comes into view.
     (b) Push the line key adjacent to the GND SCANNING indication, the GROUND SCANNING menu page comes into view.
       1 If there is a maintenance message, go to the Para. Fault Isolation.
       2 If the maintenance message does not come into view again, do the component and harness intermittent for guidance troubleshooting intermittent faults (Ref. TSM TASK 71-00-00-810-835).
         a If you find no fault, send the engine back to service. Monitor the engine to make sure that the maintenance message does not come into view again.
4. Fault Isolation
WARNING: BE CAREFUL WHEN YOU DO WORK ON THE ENGINE AFTER SHUTDOWN. THE ENGINE CAN STAY HOT FOR A LONG TIME. IF YOU DO NOT OBEY THIS WARNING, INJURY CAN OCCUR.
CAUTION: MAKE SURE YOU REMOVE ELECTRICAL POWER FROM THE EEC BEFORE YOU REMOVE THE ELECTRICAL CONNECTORS. IF YOU DO NOT OBEY THIS INSTRUCTION, DAMAGE TO THE EEC CAN OCCUR.
Subtask 30-21-00-810-071-A ** ON A/C NOT FOR ALL
A. If there is confirmation of the fault:
   (1) Open the right thrust-reverser cowl-door AMM 78-36-00-010-802.
     (a) If the fault continues:
   (2) If the fault continues:
  • Use PLIERS - JAWED, SOFT to disconnect electrical connector P13 of the EEC.
  • Examine electrical connector P13 of the EEC for bent pins, contamination or corrosion or visual signs of damage.
     (a) If you find damage on electrical connector P13:
     (b) If you find no damage on electrical connector P13:
  • Do a continuity check of the W04 harness AWM 715134 between:
    . Pin P13/q of the EEC and pin P17/12 of the NAI fan pressure-transducer (4003DN)
    . Pin P13/BB of the EEC and pin P17/4 of the NAI fan pressure-transducer (4003DN)
    . Pin P13/p of the EEC and pin P17/3 of the NAI fan pressure-transducer (4003DN)
    . Pin P13/T of the EEC and pin P17/11 of the NAI fan pressure-transducer (4003DN).
       1 If there is no continuity:
       2 If there is continuity:
Use PLIERS - JAWED, SOFT to disconnect electrical connector P14 of the EEC.
  • Examine electrical connector P14 of the EEC for bent pins, contamination or corrosion or signs of damage.
         a If you find damage on electrical connector P14:
         b If you find no damage on electrical connector P14:
  • Do a continuity check AWM 715134 of the W03 harness between:
    . Pin P14/q of the EEC and P106/11 of 4100VC
    . Pin P14/BB of the EEC and P106/12 of 4100VC
    . Pin P14/p of the EEC and P106/25 of 4100VC
    . Pin P14/T of the EEC and P106/26 of 4100VC.
  • If there is no continuity:
  • Replace the W03 HARNESS [4087KS] AMM 73-21-63-000-802 and AMM 73-21-63-400-802.
  • Do the test given in Para. 3.
  • If there is continuity:
  • Do a continuity check of the W04 harness AWM 715134 between:
    . Pin P17/9 of the NAI fan pressure-transducer (4003DN) and J106/11 of 4100VC
    . Pin P17/8 of the NAI fan pressure-transducer (4003DN) and J106/12 of 4100VC
    . Pin P17/7 of the NAI fan pressure-transducer (4003DN) and J106/25 of 4100VC
    . Pin P17/6 of the NAI fan pressure-transducer (4003DN) and J106/26 of 4100VC.
  • If there is no continuity:
  • Replace the W04 HARNESS [4088KS] AMM 73-21-64-000-802 and AMM 73-21-64-400-802.
  • Do the test given in Para. 3.
   (3) If the fault continues:
   (4) If the fault continues:
5. Close-up
Subtask 30-21-00-942-063-A ** ON A/C NOT FOR ALL
A. Put the aircraft back to its initial configuration.
   (1) Make sure that the work area is clean and clear of tools and other items.
     (a) Close the right thrust-reverser cowl-door AMM 78-36-00-410-802.
[Rev.8 from Aug 2018] 2026.04.04 04:29:32 UTC
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