HPC SVA - LDVT Disagreement Failure

TASK 75-31-00-810-814-A
HPC SVA - LDVT Disagreement Failure

1. Possible Causes

PRIMARY ACTUATOR-HPC STATOR VANE [4052KS]
ACTUATOR - HPC STATOR VANE, SECONDARY [4053KS]
W04 HARNESS [4088KS]
WC08 HARNESS-CORE [4094KS]
W03 HARNESS [4087KS]
WC10 HARNESS-CORE [4011KS]
[4000KS]

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

B. Referenced Information

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 73-21-00-710-806	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 73-21-68-000-802	Removal of the EEC Wiring Harness (WC08)
AMM 73-21-68-400-802	Installation of the EEC Wiring Harness (WC08)
AMM 73-21-69-000-802	Removal of the EEC Wiring Harness (WC10)
AMM 73-21-69-400-802	Installation of the EEC Wiring Harness (WC10)
AMM 75-31-02-000-801	Removal of the High Pressure Compressor (HPC) Stator Vane Actuator (SVA) Primary
AMM 75-31-02-400-801	Installation of the High Pressure Compressor (HPC) Stator Vane Actuator (SVA) Primary
AMM 75-31-04-000-801	Remove the High Pressure Compressor (HPC) Stator Vane Actuator (SVA) Secondary Unit
AMM 75-31-04-400-801	Install the High Pressure Compressor (HPC) Stator Vane Actuator (SVA) Secondary Unit
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
W03/WC10 Interconnect Wiring Harnesses
HPC SVA Secondary Wiring Harnesses
HPC SVA Secondary Wiring Schematic
W04/WC08 Interconnect Wiring Harnesses
HPC SVA Primary Wiring Harnesses
HPC SVA Channel A and Channel B Wiring Schematic
EEC Wiring Harnesses

3. Fault Confirmation
Subtask 75-31-00-710-063-A ** ON A/C NOT FOR ALL

A. Do the EEC system test to confirm this fault. Refer to FADEC self test AMM 73-21-00-710-806.

NOTE: The Electronic Engine Control (EEC) has detected that the Linear Variable Differential Transducer (LVDT) circuit for the High Pressure Compressor (HPC) Stator Vane Actuator (SVA) primary in channel A does not agree with the LVDT circuit for the HPC SVA secondary in channel B. The HPC SVA primary is mounted on the HPC bellcrank mount bracket located at the 2 o'clock position. The HPC SVA secondary is mounted on the HPC bellcrank mount bracket and the forward case mount bracket located at the 7 o'clock position.

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).

(1) If the maintenance message does not come back, examine the harnesses and electrical connectors as described in the component and harness intermittent fault isolation procedure (Ref. TSM TASK 71-00-00-810-835).
(a) If no problems are found, return the engine to service. 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

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 75-31-00-810-066-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) Replace PRIMARY ACTUATOR-HPC STATOR VANE [4052KS] AMM 75-31-02-000-801 and AMM 75-31-02-400-801.
(a) Do the test given in Para. 3.
(3) If the fault continues:
(a) Replace ACTUATOR - HPC STATOR VANE, SECONDARY [4053KS] AMM 75-31-04-000-801 and AMM 75-31-04-400-801.
(b) Do the test given in Para. 3.
(4) If the fault continues:
(a) Examine the W04 (4088KS), WC08 (4094KS), W03 (4087KS) and WC10 (4011KS) harnesses, connectors P5 (4000KS-P5) and P6 (4000KS-P6) - EEC (4000KS), interconnect J108 (4111VC)/P108 (4111VC-A), interconnect J110 (4110VC)/P110 (4110VC-A), connectors P25 (4052KS-P25) - HPC SVA primary (4052KS) and connector P29 (4053KS-P29)- HPC SVA secondary (4053KS), for problems which are possible between the EEC (4000KS), the HPC SVA primary (4052KS) and the HPC SVA secondary (4053KS).
(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 harnesses or connectors:
1 Replace W04 HARNESS [4088KS] AMM 73-21-64-000-802 and AMM 73-21-64-400-802, or
2 Replace WC08 HARNESS-CORE [4094KS] AMM 73-21-68-000-802 and AMM 73-21-68-400-802, or
3 Replace W03 HARNESS [4087KS] AMM 73-21-63-000-802 and AMM 73-21-63-400-802, or
4 Replace WC10 HARNESS-CORE [4011KS] AMM 73-21-69-000-802 and AMM 73-21-69-400-802.
5 Do the test given in Para. 3.
(5) If no problems are found with the harnesses or the fault continues, use a PLIERS - JAWED, SOFT to disconnect the electrical connectors P5 (4000KS-P5) and P6 (4000KS-P6) from the EEC (4000KS), interconnect J108 (4111VC)/P108 (4111VC-A), interconnect J110 (4110VC)/P110 (4110VC-A) and connector P25 (4052KS-P25) from the HPC SVA primary (4052KS) and connector P29 (4053KS-P29) from the HPC SVA secondary (4053KS).
(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 connectors P5 (4000KS-P5) and P6 (4000KS-P6) to the EEC (4000KS), interconnect J108 (4111VC)/P108 (4111VC-A), interconnect J110 (4110VC)/P110 (4110VC-A) and connector P25 (4052KS-P25) to the HPC SVA primary (4052KS) and connector P29 (4053KS) to the HPC SVA secondary (4053KS).
(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), interconnect J108 (4111VC)/P108 (4111VC-A) and connector P25 (4052KS-P25) from the HPC SVA primary (4052KS). Use a MULTIMETER - STANDARD to test the HPC SVA primary (4052KS) LVDT circuits in the harnesses. Refer to Table 1. 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: HPC SVA Primary LVDT Channel A Connector Contacts

W04 (4088KS) Harness P5 (4000KS-P5) EEC(4000KS) Connector Contacts	W04 (4088KS) Harness J108 (4111VC) Connector Contacts	WC08 (4094KS) Harness P108 (4111VC-A) Connector Contacts	WC08 (4094KS) Harness P25 (4052KS-P25) HPC SVA Primary (4052KS) Connector Contacts
JJ	20	20	8
x	21	21	9
e	6	6	12
C	7	7	3
D	19	19	11

(b) If a problem is found with the harnesses or connectors:
1 Replace W04 HARNESS [4088KS] AMM 73-21-64-000-802 and AMM 73-21-64-400-802, or
2 Replace WC08 HARNESS-CORE [4094KS] AMM 73-21-68-000-802 and AMM 73-21-68-000-802.
3 Do the test given in Para. 3.
(7) If no problems with the harnesses are found or the fault continues:
(a) Disconnect the electrical connector P6 (4000KS-P6) from the EEC (4000KS), interconnect J110 (4110VC)/P110(4110VC-A) and connector P29 (4053KS-P29) from the HPC SVA secondary (4053KS). Use a MULTIMETER - STANDARD to test the HPC SVA secondary (4053KS) LVDT circuits in the harnesses. Refer to 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 2: HPC SVA Secondary LVDT Channel B Connector Contacts

W03 (4087KS) HarnessP6 (4000KS-P6) EEC (4000KS) Connector Contacts	W03 (4087KS) Harness J110 (4110VC) Connector Contacts	WC10 (4011KS) Harness P110 (4110VC-A) Connector Contacts	WC10 (4011KS) Harness P29 (4053KS-P29) HPC SVA Secondary (4053KS) Connector Contacts
JJ	8	8	5
x	9	9	4
e	2	2	2
C	3	3	1
D	10	10	3

(b) If a problem is found with the harnesses or connectors:
1 Replace W03 HARNESS [4087KS] AMM 73-21-63-000-802 and AMM 73-21-63-400-802, or
2 Replace WC10 HARNESS-CORE [4011KS] AMM 73-21-69-000-802 and AMM 73-21-69-400-802.
3 Do the test given in Para. 3.
(8) If no problems are found with the harnesses or the fault continues:
(a) Replace the [4000KS] AMM 73-21-01-000-801 and AMM 73-21-01-400-801.
(b) Do the test given in Para. 3.

5. Close-up
Subtask 75-31-00-860-058-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.

[Rev.8 from Aug 2018] 2026.04.04 04:37:20 UTC