W DOC AIRBUS | TSM A320F

NAI Valves Failed Open with the NAI Pushbutton Switch Released on Channels A and B (Two NAI Valves are Failed Open)

TASK 30-21-00-810-812-A
NAI Valves Failed Open with the NAI Pushbutton Switch Released on Channels A and B (Two NAI Valves are Failed Open)

1. Possible Causes
  • W04 HARNESS [4088KS]
  • NAI SOLENOID BLOCK [4190KS]
  • damaged tubes
  • PRESS XDCR-ENGINE AIR INTAKE ANTI ICE, 2 [4003DN]
  • W03 HARNESS [4087KS]
  • NACELLE ANTI-ICE UPPER VALVE AND ATTACHMENT HARDWARE [4010DN]
  • NACELLE ANTI-ICE LOWER VALVE AND ATTACHMENT HARDWARE [4011DN]
  • [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 30-21-00-440-803
Reactivation of the NAI Upper Valve with the Thrust Reverser Door Open
AMM 30-21-00-440-804
Reactivation of the NAI Lower Valve with the Thrust Reverser Door Open
AMM 30-21-00-710-002
Operational Test of the Engine Air Intake Ice Protection (with the Engines in operation)
AMM 30-21-12-000-801
Removal of the Nacelle Anti-Ice Sense-Tubes
AMM 30-21-12-400-801
Installation of the Nacelle Anti-Ice Sense-Tubes
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 30-21-51-000-803
Removal of the Lower Anti-Ice Valve
AMM 30-21-51-400-802
Installation of the Upper Anti-Ice Valve
AMM 30-21-51-400-803
Installation of the Lower Anti-Ice Valve
AMM 31-32-00-860-012
Procedure to Get Access to the SYSTEM REPORT/TEST/ENG Page
AWM 715134
AMM 73-21-00-710-806
Test No.7 - EEC Operation Test (Self Test)
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 30-21-00-710-067-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.
NOTE: Hot air leakage is a dual fault reported by both channel.
The EEC 1(2) CHAN A(B) page come 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 the 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 and 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 30-21-00-810-061-A ** ON A/C NOT FOR ALL
A. If there is confirmation of the fault:
   (1) Do the EEC system test AMM 73-21-00-710-806.
   (2) Make sure that there is no fault message shown in the SRM fault report AMM 31-32-00-860-012:
  • ENG1A-2012-DOWNSTREAM NAI PT FAIL, and
  • ENG1B-2013-DOWNSTREAM NAI PT FAIL.
   (3) Make sure that there is no fault message shown in the last leg report AMM 31-32-00-860-012.
  • ENG1A-2030-NAI-DOWNSTREAM SOL FAIL, and
  • ENG1B-2032-NAI-DOWNSTREAM SOL FAIL.
   (4) Open the right thrust-reverser cowl-door AMM 78-36-00-010-802.
   (5) Make sure that the NAI downstream valve is activated:
     (a) If the NAI downstream valve is not activated, do the reactivation of the NAI downstream valve AMM 30-21-00-440-804.
  • Do the test given in Para. 3.
   (6) Make sure that the NAI upstream valve is activated:
     (a) If the NAI upstream valve is not activated, do the reactivation of the NAI upstream valve AMM 30-21-00-440-803.
  • Do the test given in Para. 3.
   (7) Make sure that the connector P58 in receptacle J58 of the NAI upstream SOV of the NAI solenoids block is correctly engaged.
     (a) If it is not correctly engaged, engage it.
  • Do the test given in Para. 3.
     (b) If you find damage or if fault continues:
  • Disconnect electrical connector P58 of the NAI upstream SOV of the NAI solenoids block.
  • Examine electrical connector P58 of the NAI upstream SOV bent pins, contamination, corrosion or visual signs of damage.
       1 If you find damage on electrical connector P58:
     (c) If you find no damage on electrical connector P58 or if fault continues:
  • Disconnect electrical connector P58 of the NAI upstream SOV of the NAI solenoids block.
  • Examine electrical receptacle J58 of the NAI upstream SOV for bent pins, contamination, corrosion or visual signs of damage.
       1 If you find damage on electrical receptacle J58 :
       2 If you find no damage on receptacle J58:
  • On receptacle J58 of the NAI upstream SOV, do a resistance check AWM 715134 between:
    . Pin J58/1 and pin J58/2 of the NAI solenoids block
    . Pin J58/1 and pin J58/2 of the NAI solenoids block.
         a If the resistance is not between 20 and 40 ohm:
         b If the resistance is between 20 and 40 ohm:
  • Do a check the NAI upstream valve sense-line after segment, mid segment and forward segment along the entire length for damage.
  • Do a check of the NAI downstream valve sense-line after segment, mid segment and forward segment along the entire length for damage.
  • Do a check of the NAI core pressure-transducer sense-line mid segment and forward segment along the entire length for damage.
  • Do a check of the interface of the NAI core pressure-transducer sense line for cracking or damage.
    If the NAI sense tubes are not correctly installed or damaged:
  • Replace the damaged tubes AMM 30-21-12-000-801 and AMM 30-21-12-400-801.
  • Do the test given in Para. 3.
   (8) Make sure that electrical connector P17 of the W04 harness is correctly engaged in receptacle J17 of the NAI fan pressure-transducer.
  • If it is not correctly engaged, engage it.
  • Do the test given in Para. 3.
     (a) If the fault continues, or if electrical connector P17 is correctly engaged PLIERS - JAWED, SOFT to disconnect electrical connector P17 from the receptacle J17 of the NAI fan pressure-transducer:
  • Examine receptacle J17 of the NAI fan pressure-transducer for bent pins, contamination or corrosion or signs of damage.
       1 If you find damage:
       2 If you find no damage :
  • On receptacle J17 of the NAI fan pressure transducer, do a resistance check AWM 715134 between:
    . Pin J17/4 and pin J17/12 of the NAI fan pressure-transducer
    . Pin J17/8 and pin J17/9 of the NAI fan pressure-transducer.
         a If the resistance is not between 1.4 and 12 kohm:
         b If the resistance is between 1.4 and 12 kohm:
  • On receptacle J17 of the NAI fan pressure-transducer, do a resistance check AWM 715134 between:
    . Pin J17/3 and pin J17/11 of the NAI fan pressure-transducer
    . Pin J17/6 and pin J17/7 of the NAI fan pressure-transducer.
         c If the resistance is not between 350 ohm and 2.5 kohm:
         d If the resistance is between 350 ohm and 2.5 kohm:
  • Examine electrical connector P17 of the W04 harness for bent pins, contamination, corrosion or visual signs of damage.
  • If you find damage on electrical connector P17:
  • Replace W04 HARNESS [4088KS] AMM 73-21-64-000-802 and AMM 73-21-64-400-802.
  • Do the test given in Para. 3.
  • If you find no damage on electrical connector P17 or the fault continues, use PLIERS - JAWED, SOFT to disconnect electrical connectors P14 from the EEC.
  • Do a continuity check AWM 715134 of the W03 harness between:
    . Pin P14/q of the EEC and pin P106/11 of 4100VC
    . Pin P14/BB of the EEC and pin P106/12 of 4100VC
    . Pin P14/p of the EEC and pin P106/25 of 4100VC
    . Pin P14/T of the EEC and pin 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 AWM 715134 of the W04 harness between:
    . Pin J106/11 of 4100VC and P17/9 of the of the NAI fan pressure-transducer
    . Pin J106/12 of 4100VC and P17/8 of the of the NAI fan pressure-transducer
    . Pin J106/25 of 4100VC and P17/7 of the of the NAI fan pressure-transducer
    . Pin J106/26 of 4100VC and P17/6 of the of the NAI fan pressure-transducer.
  • If there is no continuity:
  • Replace W04 HARNESS [4088KS] AMM 73-21-64-000-802 and AMM 73-21-64-400-802.
  • Do the test given in Para. 3.
  • If there is continuity:
    Use PLIERS - JAWED, SOFT to disconnect electrical connectors P13 from the EEC.
  • Do a continuity check AWM 715134 of the W04 harness between:
    . Pin P13/q of the EEC and pin P17/12 of the NAI fan pressure-transducer
    . Pin P13/BB of the EEC and pin P17/4 of the NAI fan pressure-transducer
    . Pin P13/p of the EEC and pin P17/3 of the NAI fan pressure-transducer
    . Pin P13/T of the EEC and pin P17/11 of the NAI fan pressure-transducer.
  • 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.
  • If there is continuity:
  • Replace the NACELLE ANTI-ICE UPPER VALVE AND ATTACHMENT HARDWARE [4010DN] AMM 30-21-51-000-802 and AMM 30-21-51-400-802.
  • Do the test given in Para. 3.
   (9) If the fault continues:
   (10) If the fault continues:
5. Close-up
Subtask 30-21-00-942-053-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 04:29:31 UTC
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