DOC AIRBUS | TSM A320FFailure of the HPTCC Valve Channel A on Engine 2
TASK 75-21-00-810-804-A
Failure of the HPTCC Valve Channel A on Engine 2
1. Possible Causes
A. Referenced Information
3. Fault Confirmation
Subtask 75-21-00-710-056-D ** ON A/C NOT FOR ALL
Subtask 75-21-00-810-055-E ** ON A/C NOT FOR ALL
[Rev.8 from Aug 2018]
2026.04.04 04:37:01 UTC
Failure of the HPTCC Valve Channel A on Engine 2
1. Possible Causes
TCC sensor(s) High Pressure Turbine Active Clearance Control (HPTACC) Valve - HMU-2 [4000KC2]
- ECU [4000KS]
- harness J7
- harness HJ7
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 73-21-50-000-006 | Removal of J7 Harness |
| AMM 73-21-50-000-040 | Removal of the HJ7 Harness for SAC Engines |
| AMM 73-21-50-210-001 | Visual Inspection of the Wiring Harness |
| AMM 73-21-50-210-002 | Visual Inspection of the Wiring Harnesses |
| AMM 73-21-50-400-006 | Installation of the J7 Harness |
| AMM 73-21-50-400-040 | Installation of the HJ7 Harness for SAC Engines |
| 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 73-21-70-000-001 | Removal of the High Pressure Turbine Clearance Control (HPTCC) Sensor |
| AMM 73-21-70-000-002 | Removal of the High Pressure Turbine Clearance Control (HPTCC) Sensor |
| AMM 73-21-70-400-001 | Installation of the High Pressure Turbine Clearance Control (HPTCC) Sensor |
| AMM 73-21-70-400-002 | Installation of the High Pressure Turbine Clearance Control (HPTCC) Sensor |
| 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 75-21-00-710-056-D ** ON A/C NOT FOR ALL
A. Do the operational test of the FADEC 2A on the ground (with engine motoring) AMM 73-29-00-710-040.
Subtask 75-21-00-710-056-E ** ON A/C NOT FOR ALL A. Do the operational test of the FADEC 2A on the ground (with engine motoring) AMM 73-29-00-710-040.
4. Fault IsolationSubtask 75-21-00-810-055-E ** ON A/C NOT FOR ALL
A. The failure message is triggered if there is a difference between the actual position and the feedback position of the valve of more than 5% and the fault continues for more than 7 seconds.
(1) If the failure message HPTC VLV (POS), HMU on channel 2A is not confirmed:
(a) No maintenance action required.
(2) If the failure message HPTC VLV (POS), HMU on channel 2A is not confirmed but is repetitive:
(a) Do the following trouble shooting at next maintenance opportunity:
1 Do a check of the Post Flight Report (PFR) and the Schedule Maintenance Report (SMR)/Class 3 report for TCC SNSR, J13, ECU.
If the failure message is present:
(a) Disconnect the harness J7 from the ECU and do a check of resistance between:
. pins 23 and 24 (17 to 23 Ohms).
1 If the resistance values are in the specified limits:
Subtask 75-21-00-810-055-F ** ON A/C NOT FOR ALL (1) If the failure message HPTC VLV (POS), HMU on channel 2A is not confirmed:
(a) No maintenance action required.
(2) If the failure message HPTC VLV (POS), HMU on channel 2A is not confirmed but is repetitive:
(a) Do the following trouble shooting at next maintenance opportunity:
1 Do a check of the Post Flight Report (PFR) and the Schedule Maintenance Report (SMR)/Class 3 report for TCC SNSR, J13, ECU.
If the failure message is present:
- disconnect the
TCC sensor(s) .
NOTE: Engines post SB 73-129 are equipped with only one sensor.
- Do a cleaning of the harness connectors and receptacles using a bristle brush with stoddart solvent (CP 2011) AMM 73-21-50-210-001.
- reconnect the connectors to the
TCC sensor(s) .
NOTE: Tighten the connector by hand plus one eighth of a turn. If necessary use soft nose pliers.
a If the fault continues: - replace the
TCC sensor(s) AMM 73-21-70-000-001 and AMM 73-21-70-400-001.
NOTE: Engines post SB 73-129 are equipped with only one sensor.
2 If the fault continues: - replace the
High Pressure Turbine Active Clearance Control (HPTACC) 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.
- replace the harness J7 AMM 73-21-50-000-006 and AMM 73-21-50-400-006.
(a) Disconnect the harness J7 from the ECU and do a check of resistance between:
. pins 23 and 24 (17 to 23 Ohms).
1 If the resistance values are in the specified limits:
- replace the
High Pressure Turbine Active Clearance Control (HPTACC) 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.
- replace the harness J7 AMM 73-21-50-000-006 and AMM 73-21-50-400-006.
- disconnect the harness J7 from the HMU and do a check of the HMU resistance between:
. pins 23 and 24 (17 to 23 Ohms).
- replace the harness J7 AMM 73-21-50-000-006 and AMM 73-21-50-400-006.
- replace the HMU-2 [4000KC2] AMM 73-21-10-000-001 and AMM 73-21-10-400-001.
NOTE: Tighten the connector by hand plus one eighth of a turn. If necessary use soft nose pliers.
A. The failure message is triggered if there is a difference between the actual position and the feedback position of the valve of more than 5% and the fault continues for more than 7 seconds.
(1) If the failure message HPTC VLV (POS), HMU on channel 2A is not confirmed:
(a) No maintenance action required.
(2) If the failure message HPTC VLV (POS), HMU on channel 2A is not confirmed but is repetitive:
(a) Do the following trouble shooting at next maintenance opportunity:
PRE SB 73-0268
1 Do a check of the Post Flight Report (PFR) and the Schedule Maintenance Report (SMR)/Class 3 report for TCC SNSR, J13, ECU.
If the failure message is present:
END OF PRE SB 73-0268
(a) Disconnect the harness HJ7 from the ECU and do a check of resistance between:
. pins 23 and 24 (17 to 23 Ohms).
1 If the resistance values are in the specified limits:
Subtask 75-21-00-710-057-D ** ON A/C NOT FOR ALL (1) If the failure message HPTC VLV (POS), HMU on channel 2A is not confirmed:
(a) No maintenance action required.
(2) If the failure message HPTC VLV (POS), HMU on channel 2A is not confirmed but is repetitive:
(a) Do the following trouble shooting at next maintenance opportunity:
PRE SB 73-0268
1 Do a check of the Post Flight Report (PFR) and the Schedule Maintenance Report (SMR)/Class 3 report for TCC SNSR, J13, ECU.
If the failure message is present:
- disconnect the
TCC sensor(s) .
NOTE: Engines post SB 73-046 are equipped with only one sensor.
- Do a cleaning of the harness connectors and receptacles using a bristle brush with stoddart solvent (CP 2011) AMM 73-21-50-210-002.
- reconnect the connectors to the
TCC sensor(s) .
NOTE: Tighten the connector by hand plus one eighth of a turn. If necessary use soft nose pliers.
a If the fault continues: - replace the
TCC sensor(s) AMM 73-21-70-000-002 and AMM 73-21-70-400-002.
NOTE: Engines post SB 73-046 are equipped with only one sensor.
2 If the fault continues: END OF PRE SB 73-0268
- replace the
High Pressure Turbine Active Clearance Control (HPTACC) 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.
- replace the harness HJ7 AMM 73-21-50-000-040 and AMM 73-21-50-400-040.
(a) Disconnect the harness HJ7 from the ECU and do a check of resistance between:
. pins 23 and 24 (17 to 23 Ohms).
1 If the resistance values are in the specified limits:
- replace the
High Pressure Turbine Active Clearance Control (HPTACC) 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.
- replace the harness HJ7 AMM 73-21-50-000-040 and AMM 73-21-50-400-040.
- disconnect the harness HJ7 from the HMU and do a check of the HMU resistance between:
. pins 23 and 24 (17 to 23 Ohms).
- replace the harness HJ7 AMM 73-21-50-000-040 and AMM 73-21-50-400-040.
- replace the HMU-2 [4000KC2] AMM 73-21-10-000-002 and AMM 73-21-10-400-002.
NOTE: Tighten the connector by hand plus one eighth of a turn. If necessary use soft nose pliers.
B. Do the test given in Para. 3.
(1) No additional maintenance action is required if the fault is not confirmed.
(2) Continue the fault isolation procedure if the fault continues.
(1) No additional maintenance action is required if the fault is not confirmed.
(2) Continue the fault isolation procedure if the fault continues.