DOC AIRBUS | TSM A320FFailure of the HPC Stage 7 Solenoid Valve on Engine 1
1. Possible Causes
NOTE: This task is to troubleshoot the Clear Language Message (CLM) 7TH BLD B SOL/HC/EEC1. The fault
codes (for A1 engines) or fault acronyms (for A5 engines) listed in the fault confirmation section below will
help you to focus on the correct cause of this CLM.
· VALVE-HPC STAGE 7 SOLENOID ( 4020KS1 )
· EEC ( 4000KS )
2 Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment
REFERENCE QTY DESIGNATION
No specific AR WARNING NOTICE(S)
B. Referenced Information
REFERENCE DESIGNATION
Ref. AMM 24-41-00-861-002 Energize the Aircraft Electrical Circuits from the External Power
Ref. AMM 24-41-00-862-002 De-energize the Aircraft Electrical Circuits Supplied from the External
Power
Ref. AMM 31-60-00-860-002 EIS Stop Procedure
Ref. AMM 70-23-15-912-010 Connection of Electrical Connectors
Ref. AMM 71-13-00-410-010 Closing of the Fan Cowls 437AL(447AL),438AR(448AR)
Ref. AMM 71-50-00-210-010 Wire Harness Visual Inspection - All Power Plant Electrical Cables
Ref. AMM 73-22-00-710-040 Operational Test of the FADEC SYSTEM on the Ground
Ref. AMM 73-22-34-000-010 Removal of the Electronic Engine Control (EEC)
Ref. AMM 73-22-34-400-010 Installation of the Electronic Engine Control (EEC)
Ref. ASM 73-25-18
Ref. AMM 75-32-51-000-010 Removal of the HPC Stage 7 Solenoid Valve
Ref. AMM 75-32-51-400-010 Installation of the HPC Stage 7 Solenoid Valve
Ref. AMM 78-30-00-440-012 Re-activation of the Thrust Reverser Hydraulic Control Unit (HCU) after
Ground Maintenance
Ref. AMM 78-32-00-410-010 Closing of the Thrust Reverser Halves
70-00-00-03-13 STANDARD PRACTICES - ENGINE - GENERAL - TASK SUPPORTING
DATA
Failure of the HPC Stage 7 Solenoid Valve on Engine 1 SHEET 1
HPC Stage 7 Solenoid Valve on Engine 1 SHEET 1
Figure 73(IAE)-00-00-991-02100-A / SHEET 1/1 - HPC Stage 7 Solenoid Valve on Engine 1 not
printed, as per printing preferences
Figure 73(IAE)-00-00-991-01300-A / SHEET 1/1 - Failure of the HPC Stage 7 Solenoid Valve on
Engine 1 not printed, as per printing preferences
3. Fault Confirmation
Subtask 73-00-00-860-102-A
A. Job Set-up
(1) Energize the aircraft electrical circuits
Ref. AMM 24-41-00-861-002 .
(2) On the overhead panel 50VU, select the ENG FADEC GND PWR 1 pushbutton switches to the ON
position.
Subtask 73-00-00-710-318-B
B. Identify Test to make sure that the Fault is Present.
NOTE: Troubleshooting can start immediately without doing the fault confirmation if this CLM was indicated
in multiple flight or ground legs.
(1) Do the CFDS message decoding to identify the fault code related to the CLM
(Ref. TSM 70-00-00-03) .
(2) If the readout gives fault acronym B7BWAF in FADEC 1A or FADEC 1B, do the FADEC system
operational test for fault confirmation Ref. AMM 73-22-00-710-040 .
(a) If the test gives the fault acronym B7BWAF in FADEC 1A or FADEC 1B or there are two or more
occurrences in fault history, continue with fault isolation Para 4.A.
(b) If the test does not give the fault acronym B7BWAF and there is no history of faults, return the
engine to service.
4. Fault Isolation
(Ref. Fig. Failure of the HPC Stage 7 Solenoid Valve on Engine 1 SHEET 1) (Ref. Fig. HPC Stage 7 Solenoid
Valve on Engine 1 SHEET 1)
Subtask 73-00-00-810-082-B
A. Fault Isolation for Fault Acronym B7BWAF
· A torque motor wrap around fault (WAF) was found in channel A or B. The circuit for the VALVE-HPC
STAGE 7 SOLENOID is open, short to ground or has a wire-to-wire short.
NOTE: At any time during this procedure, you can do the steps in Para 3. to make sure that the fault is
corrected.
NOTE: the removal and installation of the electrical connectors can correct this fault.
(1) If the fault was found in channel A, do the steps that follow:
(a) Visually examine the harness from the EEC connector (4000KS-J5) to the VALVE-HPC STAGE
7 SOLENOID (4020KS1) Ref. AMM 71-50-00-210-010 .
1 Look for harness damage.
2 Look for loose or damaged connectors.
3 Look for loose or damaged backshells.
NOTE: Loose backshells must be disassembled and examined for internal wire chafing.
4 If a problem exists with the harness, repair or replace it as necessary.
(b) If no problems are found with the harness, disconnect the electrical connector (4020KS1-A) from
the VALVE-HPC STAGE 7 SOLENOID (4020KS1) Ref. AMM 71-50-00-210-010 . Examine the
male and female parts of the connection:
1 Examine the pins and sockets (contacts) for alignment and damage.
2 Look for contacts pushed rearward into the connector face.
3 Look for elongated sockets in the connector.
NOTE: This can be done by inserting a harness connector pin into each suspect socket. You
must feel friction when inserting and removing the pin.
4 Repair as necessary.
(c) Do this electrical check of the channel A solenoid circuit in the VALVE-HPC STAGE 7
SOLENOID Ref. ASM 73-25-18.
1 Make sure that contacts 3 and 4 are not shorted to ground.
2 Make sure that contacts 3 and 4 are not shorted to other contacts in the connector.
3 Make sure that the resistance from contact 3 to contact 4 is between 41 and 77 ohms.
4 If a problem was found, remove and replace the VALVE-HPC STAGE 7
SOLENOID ( 4020KS1 ) Ref. AMM 75-32-51-000-010 and Ref. AMM 75-32-51-400-010 .
(d) If no problems were found, disconnect the electrical connector (4000KS-J5) from the EEC
(4000KS) Ref. AMM 71-50-00-210-010 . Examine the male and female parts of the connection.
1 Examine the pins and sockets (contacts) for alignment and damage.
2 Look for contacts pushed rearward into the connector face.
3 Look for elongated sockets in the connector.
NOTE: This can be done by inserting a harness connector pin into each suspect socket. You
must feel friction when inserting and removing the pin.
4 Repair as necessary.
(e) Do this electrical check of the solenoid wiring in the channel A harness. Look for:
1 Wire-to-wire shorts and shorts to ground
· Wire-to-wire short check: Measure the resistance between the wires. If the resistance is
below 100000 (100K) ohms, then the wires are shorted and need to be repaired.
· Wire-to-ground short check: Measure the resistance between the wire and the engine
metal or ground. If the resistance is below 100000 (100K) ohms, then the wire is shorted
to ground and needs to be repaired.
2 Continuity
· Continuity check: Measure the resistance between the ends of the same wire. If the
resistance is above 10 ohms, then the wire needs to be repaired.
NOTE: An incorrectly wired harness can cause this problem. When testing these circuits,
make sure that the contacts are in the correct positions in each connector as specified
in the wiring diagram.
HPC Stage 7 Solenoid Valve Circuit Channel A Harness
HPC Stage 7 Solenoid Valve (4020KS1) EEC (4000KS)
4020KS1-A 4000KS-J5
Contacts Contacts
3 q
4 p
3 If a problem exists with the harness,repair or replace it as necessary Ref. ASM 73-25-18.
(f) Install all the removed connectors Ref. AMM 70-23-15-912-010 .
(g) Do the test for this fault, listed in Para 3. for fault confirmation.
1 If the test does not give the fault acronym B7BWAF, return the engine to service.
2 If the test gives the fault acronym B7BWAF, remove and replace the VALVE-HPC STAGE 7
SOLENOID ( 4020KS1 ) Ref. AMM 75-32-51-000-010 and Ref. AMM 75-32-51-400-010 .
3 If this fault continues, remove and replace the EEC ( 4000KS ) Ref.
AMM 73-22-34-000-010 and Ref. AMM 73-22-34-400-010 .
(2) If the fault was found in channel B, do the steps that follow:
(a) Visually examine the harness from the EEC connector (4000KS-J11) to the VALVE-HPC STAGE
7 SOLENOID (4020KS1) Ref. AMM 71-50-00-210-010 .
1 Look for harness damage.
2 Look for loose or damaged connectors.
3 Look for loose or damaged backshells.
NOTE: Loose backshells must be disassembled and examined for internal wire chafing.
4 If a problem exists with the harness, repair or replace it as necessary.
(b) If no problems are found with the harness, disconnect the electrical connector (4020KS1-A) from
the VALVE-HPC STAGE 7 SOLENOID (4020KS1) Ref. AMM 71-50-00-210-010 . Examine the
male and female parts of the connection:
1 Examine pins and sockets (contacts) for alignment and damage.
2 Look for contacts pushed rearward into the connector face.
3 Look for elongated sockets in the connector.
NOTE: This can be done by inserting a harness connector pin into each suspect socket. You
must feel friction when inserting and removing the pin.
4 Repair as necessary.
(c) Do this electrical check of the channel B solenoid circuit in the VALVE-HPC STAGE 7
SOLENOID (4020KS1) Ref. ASM 73-25-18.
1 Make sure that contacts 6 and 7 are not shorted to ground.
2 Make sure that contacts 6 and 7 are not shorted to any other contacts in the connector.
3 Make sure that the resistance from contact 6 to contact 7 is between 41 and 77 ohms.
4 If a problem was found, remove and replace the VALVE-HPC STAGE 7
SOLENOID ( 4020KS1 ) Ref. AMM 75-32-51-000-010 and Ref. AMM 75-32-51-400-010 .
(d) If no problems were found, disconnect the electrical connector (4000KS-J11) from the EEC
(4000KS) Ref. AMM 71-50-00-210-010 . Examine the male and female parts of the connection.
1 Examine the pins and sockets (contacts) for alignment and damage.
2 Look for contacts pushed rearward into the connector face.
3 Look for elongated sockets in the connector.
NOTE: This can be done by inserting a harness connector pin into each suspect socket. You
must feel friction when inserting and removing the pin.
4 Repair as necessary.
(e) Do this electrical check of the solenoid wiring in the channel B harness. Look for:
1 Wire-to-wire shorts and shorts to ground
· Wire-to-wire short check: Measure the resistance between the wires. If the resistance is
below 100000 (100K) ohms, then the wires are shorted and need to be repaired.
· Wire-to-ground short check: Measure the resistance between the wire and the engine
metal or ground. If the resistance is below ground and needs to be repaired. 100000
(100K) ohms, then the wire is shorted to ground and needs to be repaired.
2 Continuity
· Continuity check: Measure the resistance between the ends of the same wire. If the
resistance is above 10 ohms, then the wire needs to be repaired.
NOTE: An incorrectly wired harness can cause this problem. When testing these circuits,
make sure that the contacts are in the correct positions in each connector as specified
in the wiring diagram.
HPC Stage 7 Solenoid Valve Circuit Channel B Harness
HPC Stage 7 Solenoid Valve (4020KS1) EEC (4000KS)
4020KS1-A 4000KS-J11
Contacts Contacts
6 q
7 p
3 If a problem exists with the harness, repair or replace it as necessary Ref. ASM 73-25-18.
(f) Install all the removed connectors Ref. AMM 70-23-15-912-010 .
(g) Do the test for this fault, listed in Para 3. for fault confirmation.
1 If the test does not give the fault acronym B7BWAF, return the engine to service.
2 If the test gives the fault acronym B7BWAF, remove and replace the VALVE-HPC STAGE 7
SOLENOID ( 4020KS1 ) Ref. AMM 75-32-51-000-010 and Ref. AMM 75-32-51-400-010 .
3 If this fault continues, remove and replace the EEC ( 4000KS ) Ref.
AMM 73-22-34-000-010 and Ref. AMM 73-22-34-400-010 .
5. Close-up
Subtask 73-00-00-860-103-A
A. Put the aircraft back to its initial configuration.
(1) Make sure that the thrust reverser halves 451AL and 452AR are closed Ref.
AMM 78-32-00-410-010 .
(2) Activate the thrust reverser HCU Ref. AMM 78-30-00-440-012 .
(3) Make sure that the fan cowls 437AL and 438AR are closed Ref. AMM 71-13-00-410-010 .
(4) Remove the WARNING NOTICE(S).
(5) On the ECAM control panel, set the UPPER DISPLAY and LOWER DISPLAY potentiometers to OFF.
Ref. AMM 31-60-00-860-002 .
(6) On the panel 50VU, push the ENG FADEC GND PWR 1 pushbutton switch.
(7) De-energize the aircraft electrical circuits
Ref. AMM 24-41-00-862-002 . [Rev.6 from Feb 2017] 2026.04.04 04:36:06 UTC