DOC AIRBUS | TSM A320FLPC SVA Position Error - Track Check Channel A
TASK 75-31-00-810-812-A
LPC SVA Position Error - Track Check Channel A
1. Possible Causes
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment
B. Referenced Information
3. Fault Confirmation
Subtask 75-31-00-710-061-A ** ON A/C NOT FOR ALL
Subtask 75-31-00-860-056-A ** ON A/C NOT FOR ALL
[Rev.8 from Aug 2018]
2026.04.04 04:40:51 UTC
LPC SVA Position Error - Track Check Channel A
1. Possible Causes
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment
| REFERENCE | QTY | DESIGNATION |
|---|---|---|
| No specific | 1 | MULTIMETER - STANDARD |
| No specific | 1 | PLIERS - JAWED, SOFT |
| REFERENCE | DESIGNATION |
|---|---|
| TSM TASK 71-00-00-810-834-A | General Troubleshooting Guidelines for Additional Troubleshooting Information |
| TSM TASK 71-00-00-810-835-A | Component and Harness Intermittent Troubleshooting Procedure for Guidance Troubleshooting Intermittent Faults |
| AMM 70-70-00-910-803 | SPOP 6 - Cleaning of the Contact Points and Wiring Harnesses |
| AMM 73-21-00-710-809 | Test No.15 - Operation Test (Dry Motor) of the FADEC System Engine Actuators |
| 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 73-21-64-000-802 | 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 75-31-00-200-803 | Mechanical Check of the Low Pressure Compressor (LPC) Stator Vane Control System |
| AMM 75-31-01-000-801 | Removal of the Low Pressure Compressor (LPC) Stator Vane Actuator (SVA) |
| AMM 75-31-01-400-801 | Installation of the Low Pressure Compressor (LPC) Stator Vane Actuator (SVA) |
| 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 |
LPC SVA Wiring HarnessesSubtask 75-31-00-710-061-A ** ON A/C NOT FOR ALL
A. Do the FADEC system actuator test to confirm this fault. Refer to FADEC system actuator test AMM 73-21-00-710-809.
(a) Fix any problems that are found.
(b) If no problems are found, return the engine to service. Monitor the engine for reoccurring maintenance message.
4. Fault IsolationNOTE: The Electronic Engine Control (EEC) has detected that the Low Pressure Compressor (LPC) Stator Vane Actuator (SVA) is not able to move to its commanded position within an acceptable period of time in channel A. The LPC SVA is mounted on the aft side of the compressor intermediate case fire containment ring located at the 9 o'clock position.
(1) If the maintenance message does not come back, do a mechanical check of the compressor stator LPC vane control system AMM 75-31-00-200-803. - Refer to the general troubleshooting guidelines for additional troubleshooting information (Ref. TSM TASK 71-00-00-810-834).
- Refer to the component and harness intermittent troubleshooting procedure for guidance troubleshooting intermittent faults (Ref. TSM TASK 71-00-00-810-835).
(a) Fix any problems that are found.
(b) If no problems are found, return the engine to service. Monitor the engine for reoccurring maintenance message.
NOTE: Position faults from fuel driven actuators may appear after servicing the engine fuel filter or other fuel system parts due to entrapped air in the system. Performing the FADEC system actuator test again will purge the air. If the actuator position faults do not clear after one or two actuator tests proceed to troubleshoot the system.
(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.
WARNING:
REFER TO THE MSDS FOR ALL MATERIAL USED AND THE MANUFACTURER'S SAFETY INSTRUCTIONS FOR ALL EQUIPMENT USED. 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 75-31-00-810-064-A ** ON A/C NOT FOR ALL A. If there is confirmation of the fault:
(1) Open the thrust reverser cowl-doors AMM 78-36-00-010-802.
(2) Do a mechanical check of the compressor stator LPC vane control system AMM 75-31-00-200-803.
(a) Repair any problems found.
(b) Do the test given in Para. 3.
(3) If no problems are found or the fault continues:
(a) Replace ACTUATOR - LPC STATOR VANE [4054KS] AMM 75-31-01-000-801 and AMM 75-31-01-400-801.
(b) Do the test given in Para. 3.
(4) If the fault continues:
(a) Examine the W04 (4088KS) harness, connector P5 (4000KS-P5) - EEC (4000KS) and connector P19 (4054KS-P19) - LPC SVA (4054KS), for problems which are possible between the EEC (4000KS) and the LPC SVA (4054KS).
(b) Inspect for harness damage.
(c) Inspect for loose or damaged connectors.
1 Replace W04 HARNESS [4088KS] AMM 73-21-64-000-802 and AMM 73-21-64-400-802.
2 Do the test given in Para. 3.
(5) If no problems are found with the harness or the fault continues, use a PLIERS - JAWED, SOFT to disconnect the electrical connector P5 (4000KS-P5) from the EEC (4000KS) and connector P19 (4054KS-P19) from the LPC SVA (4054KS).
(a) Examine the pins and sockets (contacts) for alignment and damage. Look for contacts pushed rearward into the connector face. Replace parts as necessary.
(b) Clean the contacts with contact cleaner and clean cloth per SPOP 6. Blow dry with air (at less than 30 psi) across the connector face AMM 70-70-00-910-803.
(c) Reconnect the electrical connector P5 (4000KS-P5) to the EEC (4000KS) and connector P19 (4054KS-P19) to the LPC SVA (4054KS).
(d) Do the test given in Para. 3.
(6) If the fault continues:
(a) Disconnect the electrical connector P5 (4000KS-P5) from the EEC (4000KS) and connector P19 (4054KS-P19) from the LPC SVA (4054KS). Use a MULTIMETER - STANDARD to test the LPC SVA (4054KS) Torque Motor (TM) and Linear Variable Differential Transformer (LVDT) circuits in the harnesses. Refer to Table 1 and Table 2. Look for:
1 Wire-to-wire shorts
2 Shorts to ground
3 Continuity (less than 5 ohms resistance).
Table 2: LPC SVA LVDT Channel A Connector Contacts
(b) If a problem is found with the harness or connectors:
1 Replace W04 HARNESS [4088KS] AMM 73-21-64-000-802 and AMM 73-21-64-400-802.
2 Do the test given in Para. 3.
(7) If no problems are found with the harness or the fault continues:
(a) Replace
(b) Do the test given in Para. 3.
5. Close-up(1) Open the thrust reverser cowl-doors AMM 78-36-00-010-802.
(2) Do a mechanical check of the compressor stator LPC vane control system AMM 75-31-00-200-803.
(a) Repair any problems found.
(b) Do the test given in Para. 3.
(3) If no problems are found or the fault continues:
(a) Replace ACTUATOR - LPC STATOR VANE [4054KS] AMM 75-31-01-000-801 and AMM 75-31-01-400-801.
(b) Do the test given in Para. 3.
(4) If the fault continues:
(a) Examine the W04 (4088KS) harness, connector P5 (4000KS-P5) - EEC (4000KS) and connector P19 (4054KS-P19) - LPC SVA (4054KS), for problems which are possible between the EEC (4000KS) and the LPC SVA (4054KS).
(b) Inspect for harness damage.
(c) Inspect for loose or damaged connectors.
NOTE: Loose connectors must be disconnected and examined for further wear or damage.
(d) If a problem is found with the harness or connectors: 1 Replace W04 HARNESS [4088KS] AMM 73-21-64-000-802 and AMM 73-21-64-400-802.
2 Do the test given in Para. 3.
(5) If no problems are found with the harness or the fault continues, use a PLIERS - JAWED, SOFT to disconnect the electrical connector P5 (4000KS-P5) from the EEC (4000KS) and connector P19 (4054KS-P19) from the LPC SVA (4054KS).
(a) Examine the pins and sockets (contacts) for alignment and damage. Look for contacts pushed rearward into the connector face. Replace parts as necessary.
(b) Clean the contacts with contact cleaner and clean cloth per SPOP 6. Blow dry with air (at less than 30 psi) across the connector face AMM 70-70-00-910-803.
(c) Reconnect the electrical connector P5 (4000KS-P5) to the EEC (4000KS) and connector P19 (4054KS-P19) to the LPC SVA (4054KS).
(d) Do the test given in Para. 3.
(6) If the fault continues:
(a) Disconnect the electrical connector P5 (4000KS-P5) from the EEC (4000KS) and connector P19 (4054KS-P19) from the LPC SVA (4054KS). Use a MULTIMETER - STANDARD to test the LPC SVA (4054KS) Torque Motor (TM) and Linear Variable Differential Transformer (LVDT) circuits in the harnesses. Refer to Table 1 and Table 2. Look for:
1 Wire-to-wire shorts
2 Shorts to ground
3 Continuity (less than 5 ohms resistance).
NOTE: A short to ground is found when the resistance is less than 100 000 (100K) ohms.
Table 1: LPC SVA TM Channel A Connector Contacts | W04 (4088KS) Harness P5 (4000KS-P5) EEC (4000KS) Connector Contacts | W04 (4088KS) Harness P19 (4054KS-P19) LPC SVA (4054KS) Connector Contacts |
|---|---|
| HH | 5 |
| w | 6 |
Table 2: LPC SVA LVDT Channel A Connector Contacts
| W04 (4088KS) Harness P5 (4000KS-P5) EEC (4000KS) Connector Contacts | W04 (4088KS) Harness P19 (4054KS-P19) LPC SVA (4054KS) Connector Contacts |
|---|---|
| LL | 8 |
| KK | 9 |
| f | 12 |
| y | 3 |
| E | 11 |
(b) If a problem is found with the harness or connectors:
1 Replace W04 HARNESS [4088KS] AMM 73-21-64-000-802 and AMM 73-21-64-400-802.
2 Do the test given in Para. 3.
(7) If no problems are found with the harness or the fault continues:
(a) Replace
(b) Do the test given in Para. 3.
Subtask 75-31-00-860-056-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 thrust reverser cowl-doors AMM 78-36-00-410-802.
(1) Make sure that the work area is clean and clear of tools and other items.
(a) Close the thrust reverser cowl-doors AMM 78-36-00-410-802.