DOC AIRBUS | TSM A320FRight Hand LVDT Signal Failure on Channel B
TASK 78-31-00-810-964-A
Right Hand LVDT Signal Failure on Channel B
1. Possible Causes
A. Fixtures, Tools, Test and Support Equipment
B. Referenced Information
3. Fault Confirmation
Subtask 78-31-00-710-279-A ** ON A/C NOT FOR ALL
Subtask 78-31-00-860-073-A ** ON A/C NOT FOR ALL
[Rev.8 from Aug 2018]
2026.04.04 04:38:16 UTC
Right Hand LVDT Signal Failure on Channel B
1. Possible Causes
- HARNESS - RIGHT TRAS [4132KS]
- HARNESS - PYLON T/R [4130KS]
- EEC WIRING HARNESS WF07 [4093KS]
- R UPPER ACTUATOR [3042KM1]
[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 71-13-00-410-802 | Closing of the Fan Cowl Doors |
| AWM 715136 | |
| AWM 715179 | |
| 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 73-21-67-000-801 | Removal of the Electronic Engine Control (EEC) Wiring Harness (WF07) |
| AMM 73-21-67-400-801 | Installation of the Electronic Engine Control (EEC) Wiring Harness (WF07) |
| AMM 78-31-00-710-805 | Operational Test of Thrust Reverser with MCDU |
| AMM 78-31-04-000-801 | Removal of the TRAS Locking-Feedback Actuator |
| AMM 78-31-04-400-801 | Installation of the TRAS Locking-Feedback Actuator |
| AMM 78-31-61-000-812 | Removal of the Right TRAS Monitoring Harness |
| AMM 78-31-61-000-813 | Removal of the Pylon TRAS Monitoring Harness |
| AMM 78-31-61-400-812 | Installation of the Right TRAS Monitoring Harness |
| AMM 78-31-61-400-813 | Installation of the Pylon TRAS Monitoring Harness |
| AMM 78-36-00-010-802 | Opening of the Thrust Reverser Cowl-Doors |
Subtask 78-31-00-710-279-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 78-31-00-810-308-A ** ON A/C NOT FOR ALL A. If there is confirmation of the fault:
(1) Get access to right hand upper locking-feedback actuator (3042KM1) and EEC (4000KS):
(a) Open the right thrust reverser cowl-doors AMM 78-36-00-010-802.
(2) On actuator, check for the correct engagement of connector (4004KS).
(a) Repair as necessary.
(b) Do the test given in Para. 3.
(3) If check is OK or if the fault continues, use a PLIERS - JAWED, SOFT to disconnect connector (4004KS-A) and do a visual inspection of the connector for bent pins, contamination or corrosion or other signs of damage.
(a) If you fin damage:
1 Replace HARNESS - RIGHT TRAS [4132KS] AMM 78-31-61-000-812 and AMM 78-31-61-400-812.
(4) If you find no damage or if the fault continues, disconnect connector (4055VC-A) AWM 715179.
(a) Do a visual inspection of the connector for bent pins, contamination or corrosion or other signs of damage.
(b) Do a continuity check (less than 5 ohms) between the pins of connectors (4004KS-A) and (4055VC) as follows:
(d) If you find damage:
1 Replace HARNESS - RIGHT TRAS [4132KS] AMM 78-31-61-000-812 and AMM 78-31-61-400-812.
2 Reconnect all connectors.
3 Do the test given in Para. 3.
(5) If you find no damage, disconnect connector (494VC-A) AWM 715179.
(a) Do a visual inspection of the connectors for bent pins, contamination or corrosion or other signs of damage.
(b) Do a continuity check (less than 5 ohms) between the pins of connectors (4055VC-A) and (494VC) as follows:
(d) If you find a fault:
1 Replace HARNESS - PYLON T/R [4130KS] AMM 78-31-61-000-813 and AMM 78-31-61-400-813.
2 Reconnect all connectors.
3 Do the test given in Para. 3.
(6) If your find no damage or if the fault continues, disconnect connector P8 from EEC (4000KS) AWM 715136.
(a) Do a visual inspection of the connector for bent pins, contamination or corrosion or other signs of damage.
(b) Do a continuity check (less than 5 ohms) between the pins of connectors P8 (4000KS-P8) and (494VC-A) as follows:
(d) If you find a fault:
1 Replace EEC WIRING HARNESS WF07 [4093KS] AMM 73-21-67-000-801 and AMM 73-21-67-400-801.
2 Reconnect all connectors.
3 Do the test given in Para. 3.
(7) If you find no damage on wirings or if the fault continues, check Linear Variable Differential Transducer (LVDT):
(a) Disconnect connector (4004KS-A).
(b) Do a visual inspection of the thrust reverser upper actuator (4004KS) for bent pins, contamination or corrosion or other signs of damage.
(c) At LVDT thrust reverser upper actuator (4004KS), make sure that the resistance is in the range 230 - 310 ohms between pins 8 and 7.
(d) At LVDT thrust reverser upper actuator (4004KS), make sure that the resistance is in the range 146 - 186 ohms between pins 9 and 7.
(e) At LVDT thrust reverser upper actuator (4004KS), make sure that the resistance is in the range 160 - 200 ohms between pins 2 and 7.
(f) If you find a fault:
1 Replace R UPPER ACTUATOR [3042KM1] AMM 78-31-04-000-801 and AMM 78-31-04-400-801.
2 Do the test given in Para. 3.
(8) If the fault continues:
(a) Replace
5. Close-up(1) Get access to right hand upper locking-feedback actuator (3042KM1) and EEC (4000KS):
(a) Open the right thrust reverser cowl-doors AMM 78-36-00-010-802.
(2) On actuator, check for the correct engagement of connector (4004KS).
(a) Repair as necessary.
(b) Do the test given in Para. 3.
(3) If check is OK or if the fault continues, use a PLIERS - JAWED, SOFT to disconnect connector (4004KS-A) and do a visual inspection of the connector for bent pins, contamination or corrosion or other signs of damage.
(a) If you fin damage:
1 Replace HARNESS - RIGHT TRAS [4132KS] AMM 78-31-61-000-812 and AMM 78-31-61-400-812.
(4) If you find no damage or if the fault continues, disconnect connector (4055VC-A) AWM 715179.
(a) Do a visual inspection of the connector for bent pins, contamination or corrosion or other signs of damage.
(b) Do a continuity check (less than 5 ohms) between the pins of connectors (4004KS-A) and (4055VC) as follows:
- Pin 8 and pin 10
- Pin 7 and pin 21
- Pin 9 and pin 23
- Pin 2 and pin 24.
(d) If you find damage:
1 Replace HARNESS - RIGHT TRAS [4132KS] AMM 78-31-61-000-812 and AMM 78-31-61-400-812.
2 Reconnect all connectors.
3 Do the test given in Para. 3.
(5) If you find no damage, disconnect connector (494VC-A) AWM 715179.
(a) Do a visual inspection of the connectors for bent pins, contamination or corrosion or other signs of damage.
(b) Do a continuity check (less than 5 ohms) between the pins of connectors (4055VC-A) and (494VC) as follows:
- Pin 10 and pin 35
- Pin 21 and pin 36
- Pin 23 and pin 19
- Pin 24 and pin 38.
(d) If you find a fault:
1 Replace HARNESS - PYLON T/R [4130KS] AMM 78-31-61-000-813 and AMM 78-31-61-400-813.
2 Reconnect all connectors.
3 Do the test given in Para. 3.
(6) If your find no damage or if the fault continues, disconnect connector P8 from EEC (4000KS) AWM 715136.
(a) Do a visual inspection of the connector for bent pins, contamination or corrosion or other signs of damage.
(b) Do a continuity check (less than 5 ohms) between the pins of connectors P8 (4000KS-P8) and (494VC-A) as follows:
- Pin k and pin 35
- Pin AA and pin 36
- Pin j and pin 19
- Pin L and pin 38.
(d) If you find a fault:
1 Replace EEC WIRING HARNESS WF07 [4093KS] AMM 73-21-67-000-801 and AMM 73-21-67-400-801.
2 Reconnect all connectors.
3 Do the test given in Para. 3.
(7) If you find no damage on wirings or if the fault continues, check Linear Variable Differential Transducer (LVDT):
(a) Disconnect connector (4004KS-A).
(b) Do a visual inspection of the thrust reverser upper actuator (4004KS) for bent pins, contamination or corrosion or other signs of damage.
(c) At LVDT thrust reverser upper actuator (4004KS), make sure that the resistance is in the range 230 - 310 ohms between pins 8 and 7.
(d) At LVDT thrust reverser upper actuator (4004KS), make sure that the resistance is in the range 146 - 186 ohms between pins 9 and 7.
(e) At LVDT thrust reverser upper actuator (4004KS), make sure that the resistance is in the range 160 - 200 ohms between pins 2 and 7.
(f) If you find a fault:
1 Replace R UPPER ACTUATOR [3042KM1] AMM 78-31-04-000-801 and AMM 78-31-04-400-801.
2 Do the test given in Para. 3.
(8) If the fault continues:
(a) Replace
Subtask 78-31-00-860-073-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.
(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.