Active HPC Bleed Valve Failed Open (not during Start)

TASK 75-32-00-810-844-A
Active HPC Bleed Valve Failed Open (not during Start)

1. Possible Causes

CTL SOLENOID BLEED VALVE ACTIVE - HPC [4183KS]
BLEED VALVE ACTIVE - HPC [4103JM]
SENSOR-AIR PRESSURE, HPC BLEED VALVE [4184KS]

2. Job Set-up Information
A. 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 71-00-00-860-814	Shutdown of the Engine
AMM 71-00-00-860-822	Start the Engine (Normal Manual Start)
AMM 71-00-00-860-823	Start the Engine (Normal Automatic Start)
AMM 73-21-00-710-807	Test No.6 - EEC Operation Test (Idle Test)
AMM 75-32-03-000-801	Removal of the High Pressure Compressor (HPC) Bleed Active Valve Solenoid
AMM 75-32-03-400-801	Installation of the High Pressure Compressor (HPC) Bleed Active Valve Solenoid
AMM 75-32-04-000-801	Removal of the High Pressure Compressor (HPC) Active Bleed Valve
AMM 75-32-04-400-801	Installation of the High Pressure Compressor (HPC) Active Bleed Valve
AMM 75-32-22-000-801	Removal of the HPC Bleed Valve Air Pressure Sensor - Active
AMM 75-32-22-400-801	Installation of the HPC Bleed Valve Air Pressure Sensor - Active
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
Active HPC Bleed Valve Solenoid
Active HPC Bleed Valve and Pressure Sensor

3. Fault Confirmation
Subtask 75-32-00-710-099-A ** ON A/C NOT FOR ALL

A. Do an engine run to idle to confirm this fault AMM 71-00-00-860-822 or AMM 71-00-00-860-823.
(1) Shutdown the engine AMM 71-00-00-860-814.
(2) On MCDU screen, check if the fault is displayed on ground scanning report.

NOTE: The Electronic Engine Control (EEC) channel A and channel B have detected that the active High Pressure Compressor (HPC) bleed valve is failed in the open position. The active HPC bleed valve solenoid is attached to the HPC case located at the 11:30 o'clock position. The active HPC bleed valve is mounted on the diffuser case located at the 3 o'clock position. The active HPC bleed Valve air pressure sensor is attached to the compressor intermediate case firewall located at the 2 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).

NOTE: The EEC will energize the active HPC bleed valve solenoid during engine start up to allow pressurized air to flow to the active HPC bleed valve. This will open the active HPC bleed valve to allow air flow into the engine core to assist with initial compression of up-stream air flow. The EEC will de-energize the active HPC bleed valve solenoid once observed idle has been reached. This will stop the flow of pressurized air and allow the active HPC bleed Valve to close.

(3) If the maintenance message does not come back, do a visual inspection around the active HPC bleed valve (4103JM) for material or conditions which could limit the movement of the active HPC bleed valve (4103JM).
(a) If no problems are found, return the engine to service. Monitor the engine for reoccurring maintenance message. (4) 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.

Subtask 75-32-00-810-101-A ** ON A/C NOT FOR ALL

A. Do the steps that follow:
(1) Open the thrust reverser cowl-doors AMM 78-36-00-010-802.
(2) Do a check of the Multipurpose Control Display Unit (MCDU) for maintenance messages related to the active HPC bleed valve solenoid (4183KS) and the active HPC bleed valve air pressure sensor (4184KS).
(a) If any faults are present, troubleshoot those faults first.
(b) Do the test given in Para. 3.
(3) Do a visual inspection around the active HPC bleed valve (4103JM) for material or conditions which could limit the movement of the active HPC bleed valve (4103JM).
(a) Repair any problems found.
(b) Do the test given in Para. 3.
(4) If no problems are found or the fault continues:
(a) Replace CTL SOLENOID BLEED VALVE ACTIVE - HPC [4183KS] AMM 75-32-03-000-801 and AMM 75-32-03-400-801.
(b) Do the test given in Para. 3.
(5) If no problems are found or the fault continues:
(a) Replace BLEED VALVE ACTIVE - HPC [4103JM] AMM 75-32-04-000-801 and AMM 75-32-04-400-801.
(b) Do the test given in Para. 3.
(6) If the fault continues:
(a) Replace SENSOR-AIR PRESSURE, HPC BLEED VALVE [4184KS] AMM 75-32-22-000-801 and AMM 75-32-22-400-801.
(b) Do the test given in Para. 3.

Subtask 75-32-00-700-051-A ** ON A/C NOT FOR ALL

B. Repair Confirmation
(1) Do an engine run to idle and look at the ground scanning report to confirm the repair of this fault AMM 73-21-00-710-807.
(a) If the fault does not return, you have fixed the fault.

5. Close-up
Subtask 75-32-00-860-062-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 04:40:53 UTC