DOC AIRBUS | TSM A320FICV Failed Open
TASK 78-31-00-810-981-A
ICV Failed Open
1. Possible Causes
A. Fixtures, Tools, Test and Support Equipment
B. Referenced Information
3. Fault Confirmation
Subtask 78-31-00-710-296-A ** ON A/C NOT FOR ALL
Subtask 78-31-00-860-091-A ** ON A/C NOT FOR ALL
[Rev.8 from Aug 2018]
2026.04.04 04:38:18 UTC
ICV Failed Open
1. Possible Causes
- pylon harness
- HCU-T/R, ENG1 [4310EG1]
- HCU-T/R, ENG2 [4310EG2]
- HARNESS-FAN, WF02 [4218KS]
- HCU PRESS SWITCH ENG 1A [102EG1]
- HCU PRESS SWITCH ENG 2A [102EG2]
- HARNESS-FAN, WF01 [4217KS]
- HCU PRESS SWITCH ENG 1B [103EG1]
- HCU PRESS SWITCH ENG 2B [103EG2]
[4000KS]
A. Fixtures, Tools, Test and Support Equipment
| REFERENCE | QTY | DESIGNATION |
|---|---|---|
| No specific | 1 | PLIERS - JAWED, SOFT |
| REFERENCE | DESIGNATION |
|---|---|
| TSM TASK 71-00-00-810-843-A | Nacelle Component and Harness Troubleshooting Procedure for Guidance Troubleshooting Intermittent Faults |
| AMM 71-13-00-010-802 | Opening of the Fan Cowl Doors |
| AMM 71-13-00-410-802 | Closing of the Fan Cowl Doors |
| AWM 715135 | |
| 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 73-21-61-000-802 | Removal of the Electronic Engine Control (EEC) Wiring Harness (WF01) |
| AMM 73-21-61-400-802 | Installation of the Electronic Engine Control (EEC) Wiring Harness (WF01) |
| AMM 73-21-62-000-802 | Removal of the EEC Wiring Harness (WF02) |
| AMM 73-21-62-400-802 | Installation of the EEC Wiring Harness (WF02) |
| AMM 78-31-00-710-805 | Operational Test of Thrust Reverser with MCDU |
| AMM 78-31-01-000-801 | Removal of the TRAS Hydraulic Control Unit (HCU) |
| AMM 78-31-01-400-801 | Installation of the TRAS Hydraulic Control Unit (HCU) |
| AMM 78-31-21-000-801 | Removal of the Hydraulic Control Unit (HCU) Pressure Switch |
| AMM 78-31-21-400-801 | Installation of the Hydraulic Control Unit (HCU) Pressure Switch |
| AWM 783611 | |
| AWM 783612 |
Subtask 78-31-00-710-296-A ** ON A/C NOT FOR ALL
A. Do the operational test of the thrust reverser with the MCDU to confirm this fault AMM 78-31-00-710-805.
(1) If the maintenance message does not come back, troubleshoot as described in the nacelle component and harness troubleshooting procedure for guidance troubleshooting intermittent faults (Ref. TSM TASK 71-00-00-810-843).
(a) Monitor the engine for reoccurring maintenance message.
(2) If the maintenance message comes back (hard fault), go to the Para. Fault Isolation.
4. Fault Isolation(1) If the maintenance message does not come back, troubleshoot as described in the nacelle component and harness troubleshooting procedure for guidance troubleshooting intermittent faults (Ref. TSM TASK 71-00-00-810-843).
(a) Monitor the engine for reoccurring maintenance message.
(2) If the maintenance message comes back (hard fault), go to the Para. 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 78-31-00-810-325-A ** ON A/C NOT FOR ALL A. If there is confirmation of the fault:
(1) Check if any other message related to TR PRESS SW FAIL comes on. If there are fault messages, troubleshoot them first.
(2) Get access to HCU, EEC and pylon junction box.
(a) Remove the access panel on the pylon to get access to the HCU:
1 FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
2 FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
(b) Open the fan cowl-doors AMM 71-13-00-010-802.
(3) On HCU, check that both pressure switches (102EG) and (103EG) are correctly installed AMM 78-31-21-400-801.
(a) Correct at necessary.
(b) Do the test given in Para. 3.
(4) If pressure switches are correctly installed or if the fault continues:
(a) Check for the correct engagement of connectors (102EG-A) and (103EG-A).
1 Correct as necessary.
2 Do the test given in Para. 3.
(5) If check OK or if the fault continues:
(a) Use a PLIERS - JAWED, SOFT to disconnect connectors (102EG-A) and (103EG-A) then do a visual inspection of the connectors for bent pins, contamination, corrosion or obvious signs of damage.
1 If you find damage, replace pylon harness :
a For ENG 1, refer to AWM 783611
b For ENG 2, refer to AWM 783612.
2 Reconnect connectors (102EG-A) and (103EG-A).
3 Do the test given in Para. 3.
(6) If you find no damage or if fault continues:
(a) Replace HCU-T/R, ENG1 [4310EG1] or HCU-T/R, ENG2 [4310EG2] AMM 78-31-01-000-801 and AMM 78-31-01-400-801.
(b) Do the test given in Para. 3.
(7) If the fault continues:
(a) Disconnect connectors (102EG-A) and P1 from EEC (4000KS) AWM 715135.
1 Do a continuity check (less than 5 ohms) between pins of connectors P1 and (102EG-A) as follows:
3 Do a continuity check (less than 5 ohms) between pins of connectors P1 and P402 as follows:
5 If any problem is found:
a Replace HARNESS-FAN, WF02 [4218KS] AMM 73-21-62-000-802 and AMM 73-21-62-400-802.
b Do the test given in Para. 3.
6 If there is continuity:
a Replace pylon harness :
c Do the test given in Para. 3.
(8) If no damage is found or fault continues:
(a) Replace HCU PRESS SWITCH ENG 1A [102EG1] or HCU PRESS SWITCH ENG 2A [102EG2] AMM 78-31-21-000-801 and AMM 78-31-21-400-801.
(b) Do the test given in Para. 3.
(9) If no damage is found or fault continues:
(a) Disconnect connectors (103EG-A) and P2 from EEC (4000KS) AWM 715135.
1 Do a continuity check (less than 5 ohms) between pins of connectors P2 and (103EG-A) as follows:
(c) Do a continuity check (less than 5 ohms) between pins of connectors P2 and P403 as follows:
(e) If any problem found:
1 Replace HARNESS-FAN, WF01 [4217KS] AMM 73-21-61-000-802 and AMM 73-21-61-400-802.
2 Do the test given in Para. 3.
(f) If there is continuity:
1 Replace pylon harness :
3 Do the test given in Para. 3.
(10) If no damage is found or fault continues:
(a) Replace HCU PRESS SWITCH ENG 1B [103EG1] or HCU PRESS SWITCH ENG 2B [103EG2] AMM 78-31-21-000-801 and AMM 78-31-21-400-801.
(b) Do the test given in Para. 3.
(11) If no problem is found or fault continues:
(a) Replace
(b) Do the test given in Para. 3.
5. Close-up(1) Check if any other message related to TR PRESS SW FAIL comes on. If there are fault messages, troubleshoot them first.
(2) Get access to HCU, EEC and pylon junction box.
(a) Remove the access panel on the pylon to get access to the HCU:
1 FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
2 FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
(b) Open the fan cowl-doors AMM 71-13-00-010-802.
(3) On HCU, check that both pressure switches (102EG) and (103EG) are correctly installed AMM 78-31-21-400-801.
(a) Correct at necessary.
(b) Do the test given in Para. 3.
(4) If pressure switches are correctly installed or if the fault continues:
(a) Check for the correct engagement of connectors (102EG-A) and (103EG-A).
1 Correct as necessary.
2 Do the test given in Para. 3.
(5) If check OK or if the fault continues:
(a) Use a PLIERS - JAWED, SOFT to disconnect connectors (102EG-A) and (103EG-A) then do a visual inspection of the connectors for bent pins, contamination, corrosion or obvious signs of damage.
1 If you find damage, replace pylon harness :
a For ENG 1, refer to AWM 783611
b For ENG 2, refer to AWM 783612.
2 Reconnect connectors (102EG-A) and (103EG-A).
3 Do the test given in Para. 3.
(6) If you find no damage or if fault continues:
(a) Replace HCU-T/R, ENG1 [4310EG1] or HCU-T/R, ENG2 [4310EG2] AMM 78-31-01-000-801 and AMM 78-31-01-400-801.
(b) Do the test given in Para. 3.
(7) If the fault continues:
(a) Disconnect connectors (102EG-A) and P1 from EEC (4000KS) AWM 715135.
1 Do a continuity check (less than 5 ohms) between pins of connectors P1 and (102EG-A) as follows:
- Pin M and pin 2
- Pin L and pin 5
- Pin j and pin 3.
3 Do a continuity check (less than 5 ohms) between pins of connectors P1 and P402 as follows:
- Pin M and pin 14
- Pin L and pin 13
- Pin j and pin 28.
5 If any problem is found:
a Replace HARNESS-FAN, WF02 [4218KS] AMM 73-21-62-000-802 and AMM 73-21-62-400-802.
b Do the test given in Para. 3.
6 If there is continuity:
a Replace pylon harness :
- For ENG 1, refer to AWM 783611
- For ENG 2, refer to AWM 783612.
c Do the test given in Para. 3.
(8) If no damage is found or fault continues:
(a) Replace HCU PRESS SWITCH ENG 1A [102EG1] or HCU PRESS SWITCH ENG 2A [102EG2] AMM 78-31-21-000-801 and AMM 78-31-21-400-801.
(b) Do the test given in Para. 3.
(9) If no damage is found or fault continues:
(a) Disconnect connectors (103EG-A) and P2 from EEC (4000KS) AWM 715135.
1 Do a continuity check (less than 5 ohms) between pins of connectors P2 and (103EG-A) as follows:
- Pin M and pin 2
- Pin L and pin 5
- Pin j and pin 3.
(c) Do a continuity check (less than 5 ohms) between pins of connectors P2 and P403 as follows:
- Pin M and pin 14
- Pin L and pin 13
- Pin j and pin 28.
(e) If any problem found:
1 Replace HARNESS-FAN, WF01 [4217KS] AMM 73-21-61-000-802 and AMM 73-21-61-400-802.
2 Do the test given in Para. 3.
(f) If there is continuity:
1 Replace pylon harness :
- For ENG 1, refer to AWM 783611
- For ENG 2, refer to AWM 783612.
3 Do the test given in Para. 3.
(10) If no damage is found or fault continues:
(a) Replace HCU PRESS SWITCH ENG 1B [103EG1] or HCU PRESS SWITCH ENG 2B [103EG2] AMM 78-31-21-000-801 and AMM 78-31-21-400-801.
(b) Do the test given in Para. 3.
(11) If no problem is found or fault continues:
(a) Replace
(b) Do the test given in Para. 3.
Subtask 78-31-00-860-091-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 fan cowl doors AMM 71-13-00-410-802.
(b) Close the pylon access panel:
1 FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
2 FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
(1) Make sure that the work area is clean and clear of tools and other items.
(a) Close the fan cowl doors AMM 71-13-00-410-802.
(b) Close the pylon access panel:
1 FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
2 FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)