DOC AIRBUS | TSM A320FLoss of the Fuel Shut-off Valve Control on Engine 2
1. Possible Causes
NOTE: This task is to troubleshoot the clear language message FMU/HC/EEC2. The fault acronyms listed in the
fault confirmation section below will help you focus on the correct cause of this clear language message.
· harness from the engine master control to the FMU (4000KC)
· FMU ( 4000KC )
· harness from the EEC connector (4000KS-J2) to the FMU (4000KC)
· harness from the EEC connector (4000KS-J3) to the FMU (4000KC)
· CTL SW-ENG/MASTER 2 ( 2KC )
· EEC ( 4000KS )
· harness from the EEC connector (4000KS-J8) to the FMU (4000KC)
· harness from the EEC connector (4000KS-J9) to the FMU (4000KC)
· harness from the engine master control to the FMU (4000KC)
· ACTUATOR-LP FUEL VALVE, ENG 2 ( 10QG )
· VALVE-LP FUEL, ENG 2 ( 13QM )
· fuel pump
2 Job Set-up Information
A. Referenced Information
REFERENCE DESIGNATION
73-00-00-810-901-B Multiple Dual Track Check Faults on the Engine 2
REFERENCE DESIGNATION
Ref. ESPM 20-45-21
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 28-24-41-000-001 Removal of the LP Fuel Valve
Ref. AMM 28-24-41-400-001 Installation of the LP Fuel Valve
Ref. AMM 28-24-51-000-001 Removal of the LP Fuel Valve Actuator
Ref. AMM 28-24-51-400-001 Installation of the LP Fuel Valve Actuator
Ref. AMM 31-10-00-700-001 Test Program after Removal/Installation of a VU panel
Ref. AMM 31-60-00-860-002 EIS Stop Procedure
Ref. AMM 70-23-15-912-010 Connection of Electrical Connectors
Ref. AMM 71-00-00-710-013 Test No.11 : High Power Assurance Test
Ref. AMM 71-00-00-710-018 Discontinued Start, Restart and Shutdown Procedures
Ref. AMM 71-00-00-710-043 Normal Engine Automatic Start Procedure
Ref. AMM 71-00-00-710-047 Normal Engine Manual Start Procedure
Ref. AMM 71-13-00-010-010 Opening 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 73-12-41-000-010 Removal of the Low Pressure (LP)/High Pressure (HP) Fuel Pump
Ref. AMM 73-12-41-400-010 Installation of the Low Pressure (LP)/High Pressure (HP) Fuel Pump
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. AMM 73-22-52-000-010 Removal of the Fuel Metering Unit (FMU)
Ref. AMM 73-22-52-400-010 Installation of the Fuel Metering Unit (FMU)
Ref. ASM 76-12-01
Ref. AMM 78-32-00-010-010 Opening of the Thrust Reverser Halves
70-00-00-03-13 STANDARD PRACTICES - ENGINE - GENERAL - TASK SUPPORTING
DATA
Fuel Shut-Off Valve SHEET 1
Figure 73(IAE)-00-00-991-00200-B / SHEET 1/1 - Fuel Shut-Off Valve not printed, as per printing
preferences
3. Fault Confirmation
Subtask 73-00-00-860-164-A
A. Job Set-Up
(1) Energize the aircraft electrical circuits
Ref. AMM 24-41-00-861-002 .
(2) On the ENG section of the maintenance panel 50VU, put the FADEC GND PWR 2 pushbutton switch
in the ON position.
Subtask 73-00-00-710-307-A
B. Identification of the Test to Make Sure that the Fault is Present
NOTE: Troubleshooting can start immediately without doing the fault confirmation if the clear language
message was indicated in multiple flight or ground legs.
(1) Do the CFDS message decoding to identify the fault acronym related to the clear language message
(Ref. TSM 70-00-00-03) .
(2) If the readout gives the fault acronym WNFILF, WOFWAF or WONWAF in FADEC 2A or FADEC 2B,
do the FADEC system operational test for fault confirmation Ref. AMM 73-22-00-710-040 .
(a) If the test gives the fault acronym WOFWAF in FADEC 2A or FADEC 2B, or there are two or
more occurrences in the fault history, continue with fault isolation Para. 4.A.
(b) If the test gives the fault acronym WONWAF in FADEC 2A or FADEC 2B, or there are two or
more occurrences in the fault history, continue with fault isolation Para. 4.A.
(c) If the test gives the fault acronym WNFILF in FADEC 2A or FADEC 2B, or there are two or more
occurrences in the fault history, continue with fault isolation Para. 4.B.
(d) If the test does not give the fault acronym WNFILF, the fault acronym WOFWAF or the fault
acronym WONWAF and there is no history of faults, return the engine to service.
(3) If the readout gives the fault acronym WOFWAI, the fault acronym WONWAI or the fault acronym
WNFILI in FADEC 2A or FADEC 2B, do the steps in Para. 3.C. for fault confirmation.
(a) If the test gives the fault acronym WOFWAI or there are two or more occurrences in the fault
history, continue with fault isolation Para. 4.A.
(b) If the test gives the fault acronym WONWAI or there are two or more occurrences in the fault
history, continue with fault isolation Para. 4.A.
(c) If the test gives the fault acronym WNFILI or there are two or more occurrences in the fault
history, continue with fault isolation Para. 4.B.
(d) If the test does not give the fault acronym WOFWAI, the fault acronym WONWAI or the fault
acronym WNFILI, and there is no history of faults, return the engine to service.
(4) If the readout gives the fault acronym WHPFLL or the fault acronym WONDFS in FADEC 2A or
FADEC 2B, do the steps in Para. 3.D. for fault confirmation.
NOTE: Multiple dual track check faults may indicate a failed fuel pump. Four control units on the
engine are driven by HP fuel: the VSV actuator, the 2.5 bleed controller, the ACOC air
modulating valve and the active clearance control actuator. If you have faults with two
or more of these units, you must follow the multiple dual track check faults procedure
(Ref. TSM 73-00-00-810-901) .
(a) If the test gives the fault acronym WHPFLL or there are two or more occurrences in the fault
history, continue with fault isolation Para. 4.C.
(b) If the test gives the fault acronym WONDFS or there are two or more occurrences in the fault
history, continue with fault isolation Para. 4.C.
(c) If the test does not give the fault acronym WHPFLL or the fault acronym WONDFS, and there is
no history of faults, return the engine to service.
Subtask 73-00-00-710-243-A
C. Test for Fault Acronym WOFWAI, the Fault Acronym WONWAI or the Fault Acronym WNFILI
(1) On the ENG section of the maintenance panel 50VU, put the FADEC GND PWR 2 pushbutton switch
in the ON position.
NOTE: This step resets the FADEC memory.
(2) Push the INIT mode key. The INIT page comes into view.
(3) Start the engine 2 by the normal engine automatic start procedure Ref. AMM 71-00-00-710-043 or
the normal engine manual start procedure Ref. AMM 71-00-00-710-047 .
NOTE: You must operate the engine for a minimum of three minutes. If not, the LAST LEG REPORT
will not be erased and the fault will not be kept again in the EEC LAST LEG REPORT.
(4) Do the shutdown of the engine 2 by the discontinued start, restart and shutdown procedure Ref.
AMM 71-00-00-710-018 .
(5) Read the LAST LEG REPORT and the scheduled maintenance report of the FADEC 2A and FADEC
2B menu on the MCDU (Ref. TSM 70-00-00-03) .
(a) Make a record of the fault message.
(b) Make a record of the channel, FADEC 2A or FADEC 2B, which found the fault.
(c) Do the CFDS message decoding and read the flight data and ground data to identify the fault
acronym.
Subtask 73-00-00-710-366-A
D. Test for Fault Acronym WHPFLL or Fault Acronym WONDFS
(1) On the ENG section of the maintenance panel 50VU, put the FADEC GND PWR 2 pushbutton switch
in the ON position.
NOTE: This action resets the FADEC memory.
(2) Do the test No. 11: High power assurance test Ref. AMM 71-00-00-710-013 .
(3) Read the LAST LEG REPORT and the scheduled maintenance report of the FADEC (2A and 2B)
menu on the MCDU (Ref. TSM 70-00-00-03) .
(a) Make a record of the failure message.
(b) Make a record of the channel FADEC 2A or FADEC 2B which found the fault.
(c) Do the CFDS message decoding to identify the fault acronym.
4. Fault Isolation
Subtask 73-00-00-810-187-A
A. Fault Isolation for Fault Acronym WOFWAF, the Fault Acronym WONWAF, the Fault Acronym WOFWAI
and the Fault Acronym WONWAI
(Ref. Fig. Fuel Shut-Off Valve SHEET 1)
A torque motor Wrap Around Fault (WAF) was found in channel A or B. The circuit for the FMU 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) Do the wiring check that follows from the FMU (4000KC) to the engine master control:
(a) Visually examine the harness from the engine master control to the FMU (4000KC) 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 as necessary.
(b) If no problems are found with the harness, disconnect the electrical connector (4000KC-A) from
the FMU (4000KC) Ref. AMM 71-50-00-210-010 . Examine the male and female parts of the
connection:
WARNING: MAKE SURE THAT THE FADEC IS DE-ENERGIZED. IF IT IS ENERGIZED,
THERE IS A RISK OF INJURY OR DAMAGE.
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 an electrical check of the engine master control shut-off valve torque motor circuit in the FMU
(4000KC) Ref. ASM 76-12-01.
1 Make sure that contacts 1 and 2 are not shorted to ground.
2 Make sure that contacts 1 and 2 are not shorted to any other contacts in connector.
3 Make sure that the resistance from contact 1 to contact 2 is between 90 and 110 ohms or 30
and 36 ohms.
4 If a problem was found, remove and replace the FMU ( 4000KC ) Ref.
AMM 73-22-52-000-010 and Ref. AMM 73-22-52-400-010 .
(d) Install all removed connectors Ref. AMM 70-23-15-912-010 .
(e) Do the test for this fault, listed in Para. 3 for fault confirmation.
1 If the test does not give the fault acronym WOFWAF, the fault acronym WONWAF, the fault
acronym WOFWAI or the fault acronym WONWAI, return the engine to service.
2 If the test gives the fault acronym WOFWAF, the fault acronym WONWAF, the fault acronym
WOFWAI or fault acronym WONWAI, continue the troubleshooting.
(2) If the fault was found in Channel A, do the following steps:
(a) Visually examine the harness from the EEC connector (4000KS-J2) to the FMU (4000KC) 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 as necessary.
(b) Visually examine the harness from the EEC connector (4000KS-J3) to the FMU (4000KC) 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 as necessary.
(c) If no problems are found with the harness, disconnect the electrical connector (4000KC-B) from
the FMU (4000KC) Ref. AMM 71-50-00-210-010 . Examine the male and female parts of the
connection:
WARNING: MAKE SURE THAT THE FADEC IS DE-ENERGIZED. IF IT IS ENERGIZED,
THERE IS A RISK OF INJURY OR DAMAGE.
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.
(d) Do this electrical check of the channel A microswitch circuit in the FMU (4000KC) Ref. ASM
76-12-01.
1 Make sure that contacts N and M are not shorted to ground.
2 Make sure that contacts N and M are not shorted to any other contacts in the connector.
3 Make sure that the resistance from contact N to contact M is between 0 and 10 ohms.
4 If a problem was found, remove and replace the FMU ( 4000KC ) Ref.
AMM 73-22-52-000-010 and Ref. AMM 73-22-52-400-010 .
(e) Do this electrical check of the channel A torque motor circuit in the FMU (4000KC) Ref. ASM
76-12-01.
1 Make sure that contacts P and S are not shorted to ground.
2 Make sure that contacts P and S are not shorted to any other contacts in the connector.
3 Make sure that the resistance from contact P to contact S is between 60 and 72 ohms
(Goodrich channels A and B) or 180 and 220 ohms (Woodward channels A and B).
4 If a problem was found, remove and replace the FMU ( 4000KC ) Ref.
AMM 73-22-52-000-010 and Ref. AMM 73-22-52-400-010 .
(f) If no problems were found, disconnect the electrical connector (4000KS-J2) 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.
(g) If no problems were found, disconnect the electrical connector (4000KS-J3) 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.
(h) Do this electrical check of the microswitch and torque motor wiring in the Channel A harness.
Look for:
1 Wire-to-wire shorts and shorts-to-ground
a 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.
b Wire-to-ground short check: Measure the resistance between the wire and 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
a 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.
Microswitch Circuit Channel A Harness
FMU (4000KC) EEC (4000KS)
4000KC-B 4000KS-J2
Contacts Contacts
N B
M C
Torque Motor Circuit Channel A Harness
FMU (4000KC) EEC (4000KS)
4000KC-B 4000KS-J3
Contacts Contacts
P W
S V
3 If a problem exists with the harness, repair or replace as necessary Ref. ASM 76-12-01.
(i) Install all removed connectors Ref. AMM 70-23-15-912-010 .
(j) Do the test for this fault, listed in Para. 3 for fault confirmation.
1 If the test does not give the fault acronym WOFWAF, the fault acronym WONWAF, the fault
acronym WOFWAI or the fault acronym WONWAI, return the engine to service.
2 If the test gives the fault acronym WOFWAF, the fault acronym WONWAF, the fault acronym
WOFWAI or the fault acronym WONWAI, remove and replace the FMU ( 4000KC ) Ref.
AMM 73-22-52-000-010 and Ref. AMM 73-22-52-400-010 .
3 If the fault continues, replace CTL SW-ENG/MASTER 2 ( 2KC ) on the 115VU Ref.
ESPM 20-45-21.
a Do a test program after the removal and installation of the VU panel Ref.
AMM 31-10-00-700-001 .
4 If the fault continues, remove and replace the EEC ( 4000KS ) Ref.
AMM 73-22-34-000-010 and Ref. AMM 73-22-34-400-010 .
(3) If the fault was found in Channel B, do the following steps:
(a) Visually examine the harness from the EEC connector (4000KS-J8) to the FMU (4000KC) 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 as necessary.
(b) Visually examine the harness from the EEC connector (4000KS-J9) to the FMU (4000KC) 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 as necessary.
(c) If no problems are found with the harness, disconnect the electrical connector (4000KC-C) from
the FMU (4000KC) Ref. AMM 71-50-00-210-010 . Examine the male and female parts of the
connection:
WARNING: MAKE SURE THAT THE FADEC IS DE-ENERGIZED. IF IT IS ENERGIZED,
THERE IS A RISK OF INJURY OR DAMAGE.
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.
(d) Do this electrical check of the channel B microswitch circuit in the FMU (4000KC) Ref. ASM
76-12-01.
1 Make sure that contacts N and M are not shorted to ground.
2 Make sure that contacts N and M are not shorted to any other contacts in the connector.
3 Make sure that the resistance from contact N to contact M is between 0 and 10 ohms.
4 If a problem was found, remove and replace the FMU ( 4000KC ) Ref.
AMM 73-22-52-000-010 and Ref. AMM 73-22-52-400-010 .
(e) Do this electrical check of the channel B torque motor circuit in the FMU (4000KC) Ref. ASM
76-12-01.
1 Make sure that contacts P and S are not shorted to ground.
2 Make sure that contacts P and S are not shorted to any other contacts in the connector.
3 Make sure that the resistance from contact P to contact S is between 60 and 72 ohms
(Goodrich channels A and B) or 180 and 220 ohms (Woodward channels A and B).
4 If a problem was found, remove and replace the FMU ( 4000KC ) Ref.
AMM 73-22-52-000-010 and Ref. AMM 73-22-52-400-010 .
(f) If no problems were found, disconnect the electrical connector (4000KS-J8) 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.
(g) If no problems were found, disconnect the electrical connector (4000KS-J9) 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.
(h) Do this electrical check of the microswitch and torque motor wiring in the Channel B harness.
Look for:
1 Wire-to-wire shorts and shorts-to-ground
a 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.
b Wire-to-ground short check: Measure the resistance between the wire and 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
a 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.
Microswitch Circuit Channel B Harness
FMU (4000KC) EEC (4000KS)
4000KC-C 4000KS-J8
Contacts Contacts
N B
M C
Torque Motor Circuit Channel B Harness
FMU (4000KC) EEC (4000KS)
4000KC-C 4000KS-J9
Contacts Contacts
P W
S V
3 If a problem exists with the harness, repair or replace as necessary Ref. ASM 76-12-01.
(i) Install all the removed connectors Ref. AMM 70-23-15-912-010 .
(j) Do the test for this fault, listed in Para. 3 for fault confirmation.
1 If the test does not give the fault acronym WOFWAF, the fault acronym WONWAF, the fault
acronym WOFWAI or fault acronym WONWAI, return the engine to service.
2 If the test gives the fault acronym WOFWAF, the fault acronym WONWAF, the fault acronym
WOFWAI or fault acronym WONWAI, remove and replace the FMU ( 4000KC ) Ref.
AMM 73-22-52-000-010 and Ref. AMM 73-22-52-400-010 .
3 If the fault continues, replace CTL SW-ENG/MASTER 2 ( 2KC ) on the 115VU Ref.
ESPM 20-45-21.
a Do a test program after the removal and installation of the VU panel Ref.
AMM 31-10-00-700-001 .
4 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 .
Subtask 73-00-00-810-168-A
B. Fault Isolation for Fault Acronym WNFILF or the Fault Acronym WNFILI
The overcurrent sens has failed or an overcurrent was found in channel A and B.
NOTE: At any time during this procedure, you can do the steps in Para. 3 to make sure that the fault is
corrected.
NOTE: Removal and installation of the electrical connectors can correct this fault.
(1) Do the wiring check that follows from the FMU (4000KC) to the engine master control:
(a) Visually examine the harness from the engine master control to the FMU (4000KC) 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 as necessary.
(b) If no problems are found with the harness, disconnect the electrical connector (4000KC-A) from
the FMU (4000KC) 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 engine master control shut-off valve torque motor circuit in the
FMU (4000KC) Ref. ASM 76-12-01.
1 Make sure that contacts 1 and 2 are not shorted to ground.
2 Make sure that contacts 1 and 2 are not shorted to any other contacts in the connector.
3 Make sure that the resistance from contact 1 to contact 2 is between 90 and 110 ohms or 30
and 36 ohms.
4 If a problem was found, remove and replace the FMU ( 4000KC ) Ref.
AMM 73-22-52-000-010 and Ref. AMM 73-22-52-400-010 .
(d) Install all the removed connectors Ref. AMM 70-23-15-912-010 .
(e) Do the test for this fault, listed in Para. 3 for fault confirmation.
1 If the test does not give the fault acronym WNFILF or the fault acronym WNFILI, return the
engine to service.
2 If the test gives the fault acronym WNFILF, or the fault acronym WNFILI, do the steps that
follow:
(2) If the fault was found in Channel A, do the following steps:
(a) Visually examine the harness from the EEC connector (4000KS-J3) to the FMU (4000KC) 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 as necessary.
(b) If no problems are found with the harness, disconnect the electrical (4000KC-B) from the FMU
(4000KC) Ref. AMM 71-50-00-210-010 . Examine the male and female parts of the connection:
WARNING: MAKE SURE THAT THE FADEC IS DE-ENERGIZED. IF IT IS ENERGIZED,
THERE IS A RISK OF INJURY OR DAMAGE.
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 torque motor circuit in the FMU (4000KC) Ref. ASM
76-12-01.
1 Make sure that contacts P and S are not shorted to ground.
2 Make sure that contacts P and S are not shorted to any other contacts in the connector.
3 Make sure that the resistance from contact P to contact S is between 60 and 72 ohms
(Goodrich channels A and B) or 180 and 220 ohms (Woodward channels A and B).
4 If a problem was found, remove and replace the FMU ( 4000KC ) Ref.
AMM 73-22-52-000-010 and Ref. AMM 73-22-52-400-010 .
(d) If no problems were found, disconnect the electrical connector (4000KS-J3) 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 torque motor wiring in the Channel A harness. Look for:
1 Wire-to-wire shorts and shorts-to-ground
a 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.
b Wire-to-ground short check: Measure the resistance between wire and 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
a 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.
Torque Motor Circuit Channel A Harness
FMU (4000KC) EEC (4000KS)
4000KC-B 4000KS-J3
Contacts Contacts
P W
S V
3 If a problem exists with the harness, repair or replace as necessary Ref. ASM 76-12-01.
(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 WNFILF or the fault acronym WNFILI, return the
engine to service.
2 If the test gives the fault acronym WNFILF or the fault acronym WNFILI, remove and replace
the FMU ( 4000KC ) Ref. AMM 73-22-52-000-010 and Ref. AMM 73-22-52-400-010 .
3 If the fault continues, replace the CTL SW-ENG/MASTER 2 ( 2KC ) on the 115VU Ref.
ESPM 20-45-21.
a Do a test program after the removal and installation of the VU panel Ref.
AMM 31-10-00-700-001 .
4 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 .
(3) If the fault was found in Channel B, do the following steps:
(a) Visually examine the harness from the EEC connector (4000KS-J9) to the FMU (4000KC) 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 as necessary.
(b) If no problems are found with the harness, disconnect the electrical connector (4000KC-C) from
the FMU (4000KC) Ref. AMM 71-50-00-210-010 . Examine the male and female parts of the
connection:
WARNING: MAKE SURE THAT THE FADEC IS DE-ENERGIZED. IF IT IS ENERGIZED,
THERE IS A RISK OF INJURY OR DAMAGE.
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 B torque motor circuit in the FMU (4000KC) Ref. ASM
76-12-01.
1 Make sure that contacts P and S are not shorted to ground.
2 Make sure that contacts P and S are not shorted to any other contacts in the connector.
3 Make sure that the resistance from contact P to contact S is between 60 and 72 ohms
(Goodrich channels A and B) or 180 and 220 ohms (Woodward channels A and B).
4 If a problem was found, remove and replace the FMU ( 4000KC ) Ref.
AMM 73-22-52-000-010 and Ref. AMM 73-22-52-400-010 .
(d) If no problems were found, disconnect the electrical connector (4000KS-J9) 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 torque motor wiring in the Channel B harness. Look for:
1 Wire-to-wire shorts and shorts-to-ground
a 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.
b Wire-to-ground short check: Measure the resistance between wire and 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
a 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.
Torque Motor Circuit Channel B Harness
FMU (4000KC) EEC (4000KS)
4000KC-C 4000KS-J9
Contacts Contacts
P W
S V
3 If a problem exists with the harness, repair or replace as necessary Ref. ASM 76-12-01.
(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 WNFILF or the fault acronym WNFILI, return the
engine to service.
2 If the test gives the fault acronym WNFILF or the fault acronym WNFILI, remove and replace
the FMU ( 4000KC ) Ref. AMM 73-22-52-000-010 and Ref. AMM 73-22-52-400-010 .
3 If the fault continues, replace the CTL SW-ENG/MASTER 2 ( 2KC ) on the 115VU Ref.
ESPM 20-45-21.
a Do a test program after the removal and installation of the VU panel Ref.
AMM 31-10-00-700-001 .
4 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 .
Subtask 73-00-00-810-283-A
C. Fault Isolation for Fault Acronym WHPFLL or the Fault Acronym WONDFS
A track-check fault was found in channel A or B. The FMU (4000KC) cannot move to its commanded
position or it is moving slower than normal.
NOTE: At any time during this procedure, you can do the steps in Para. 3 to make sure that the fault is
corrected.
NOTE: This fault is typically caused by a mechanical problem and not an electrical problem.
(1) Open the thrust reverser halves Ref. AMM 78-32-00-010-010 and fan cowls as necessary Ref.
AMM 71-13-00-010-010 .
(2) Remove and replace the FMU ( 4000KC ) Ref. AMM 73-22-52-000-010 and Ref.
AMM 73-22-52-400-010 .
(3) Do the test listed in Para. 3 for fault confirmation.
(4) If the test was satisfactory, return the engine to service.
(5) If the fault continues, remove and replace the ACTUATOR-LP FUEL VALVE, ENG 2 ( 10QG ) Ref.
AMM 28-24-51-000-001 and Ref. AMM 28-24-51-400-001 .
(6) Do the test listed in Para 3 for fault confirmation.
(a) If the test was satisfactory, return the engine to service.
(7) If the fault continues, remove and replace the VALVE-LP FUEL, ENG 2 ( 13QM ) Ref.
AMM 28-24-41-000-001 and Ref. AMM 28-24-41-400-001 .
(8) Do the test listed in Para 3 for fault confirmation.
(a) If the test was satisfactory, return the engine to service.
(9) 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 .
(10) If this fault contines, remove and replace the fuel pump Ref. AMM 73-12-41-000-010 and Ref.
AMM 73-12-41-400-010 .
(11) If this fault continues, do the following:
(a) Do the steps for fault acronym WOFWAF or fault acronym WONWAF listed in Para. 4.A above.
5. Close-up
Subtask 73-00-00-860-165-A
A. Put the aircraft back to its initial configuration.
(1) Close the thrust reverser halves, activate the thrust reverser HCU, close the fan cowls and remove
the warning notices Ref. AMM 71-50-00-210-010 .
(2) On the ECAM control panel, set the UPPER DISPLAY and LOWER DISPLAY potentiometers to OFF.
Ref. AMM 31-60-00-860-002 .
(3) On the panel 50VU, push the FADEC GND PWR 2 pushbutton switch.
(4) De-energize the aircraft electrical circuits
Ref. AMM 24-41-00-862-002 . [Rev.6 from Feb 2017] 2026.04.04 04:36:04 UTC