Failure of the HMU Torque Motor of the HPTCC Valve on Engine 2
TASK 75-21-00-810-820-A
Failure of the HMU Torque Motor of the HPTCC Valve on Engine 2
1. Possible Causes
2. Job Set-up Information
A. Referenced Information
3. Fault Confirmation
Subtask 75-21-00-710-110-A ** ON A/C NOT FOR ALL
Subtask 75-21-00-810-091-A ** ON A/C NOT FOR ALL
[Rev.8 from Aug 2018]
2026.04.04 04:37:02 UTC
Failure of the HMU Torque Motor of the HPTCC Valve on Engine 2
1. Possible Causes
2. Job Set-up Information
A. Referenced Information
| REFERENCE | DESIGNATION |
|---|---|
| AMM 73-21-10-000-001 | Removal of the Hydromechanical Unit (HMU) |
| AMM 73-21-10-000-002 | Removal of the Hydromechanical Unit (HMU) |
| AMM 73-21-10-400-001 | Installation of the Hydromechanical Unit (HMU) |
| AMM 73-21-10-400-002 | Installation of the Hydromechanical Unit (HMU) |
| AMM 73-21-60-000-001 | Removal of the Electronic Control Unit (ECU) |
| AMM 73-21-60-400-001 | Installation of the Electronic Control Unit (ECU) |
| AMM 73-29-00-710-040 | Operational Test of the FADEC on the ground (with Engine Motoring) |
| AMM 75-21-10-000-001 | Removal of the High Pressure Turbine Active Clearance Control (HPTACC) Valve |
| AMM 75-21-10-000-002 | Removal of the High Pressure Turbine Active Clearance Control (HPTACC) Valve |
| AMM 75-21-10-400-001 | Installation of the High Pressure Turbine Active Clearance Control (HPTACC) Valve |
| AMM 75-21-10-400-002 | Installation of the High Pressure Turbine Active Clearance Control (HPTACC) Valve |
Subtask 75-21-00-710-110-A ** ON A/C NOT FOR ALL
A. Do the operational test of the FADEC 2B on the ground (with engine motoring) AMM 73-29-00-710-040.
Subtask 75-21-00-710-110-B ** ON A/C NOT FOR ALL A. Do the operational test of the FADEC 2B on the ground (with engine motoring) AMM 73-29-00-710-040.
4. Fault IsolationSubtask 75-21-00-810-091-A ** ON A/C NOT FOR ALL
A. If the test gives the maintenance message HPTC VLV (BLD), HMU:
Subtask 75-21-00-810-091-B ** ON A/C NOT FOR ALL - replace the
High Pressure Turbine Clearance Control (HPTCC) valve AMM 75-21-10-000-002 and AMM 75-21-10-400-002.
- replace the HMU-2 [4000KC2] AMM 73-21-10-000-002 and AMM 73-21-10-400-002.
- replace the ECU [4000KS] AMM 73-21-60-000-001 and AMM 73-21-60-400-001.
A. If the test gives the maintenance message HPTC VLV (BLD), HMU:
Subtask 75-21-00-710-111-A ** ON A/C NOT FOR ALL - replace the
High Pressure Turbine Clearance Control (HPTCC) valve AMM 75-21-10-000-001 and AMM 75-21-10-400-001.
- replace the HMU-2 [4000KC2] AMM 73-21-10-000-001 and AMM 73-21-10-400-001.
- replace the ECU [4000KS] AMM 73-21-60-000-001 and AMM 73-21-60-400-001.
B. Do the test given in Para. 3.A.