W DOC AIRBUS | TSM A320F

Loss of the Alternator Power Supply on Engine 2 - Channel A

TASK 77-10-00-810-838-A
Loss of the Alternator Power Supply on Engine 2 - Channel A

1. Possible Causes
  • alternator stator
  • J9 harness
  • alternator rotor
  • AGB
  • ECU [4000KS]
  • HJ9 harness
2. Job Set-up Information
 A. Referenced Information
REFERENCE
DESIGNATION
AMM 72-63-00-000-001
Removal of the Accessory Gearbox Module
AMM 72-63-00-000-003
Removal of the Accessory Gearbox Assembly
AMM 72-63-00-400-001
Installation of the Accessory Gearbox Module
AMM 72-63-00-400-003
Installation of the Accessory Gearbox Assembly
AMM 73-21-30-000-001
Removal of the Control Alternator
AMM 73-21-30-000-002
Removal of the Control Alternator
AMM 73-21-30-400-001
Installation of the Control Alternator
AMM 73-21-30-400-002
Installation of the Control Alternator
AMM 73-21-50-000-008
Removal of the J9 Harness
AMM 73-21-50-000-042
Removal of the HJ9 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 73-21-50-400-008
Installation of the J9 Harness
AMM 73-21-50-400-042
Installation of the HJ9 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 73-29-00-710-040
Operational Test of the FADEC on the ground (with Engine Motoring)
AMM 79-00-00-281-002
Check of the Electrical Master Chip Detector (EMCD) for Particles
AMM 79-21-10-210-002
Check of the Lubrication Unit Magnetic Plugs and Scavenge Screens
3. Fault Confirmation
Subtask 77-10-00-710-124-A ** ON A/C NOT FOR ALL
A. Do the operational test of the FADEC 2A on the ground (with engine non motoring) AMM 73-29-00-710-040.
Subtask 77-10-00-710-124-C ** 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 77-10-00-710-124-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.
4. Fault Isolation
Subtask 77-10-00-810-091-A ** ON A/C NOT FOR ALL
A. This fault is generated if the ECU detects an open or short circuit on one or more alternator windings and N2 is greater than 58.8% (min idle).
NOTE: A possible cause of the message failure "ALT, J9, ECU" may be the result of a short circuit through J9 wires which can produce an ECU power supply deterioration. The troubleshooting steps must be performed as specified hereunder.
   (1) If the failure message ALT, J9, ECU is not confirmed:
  • do a check of the AGB lubrication unit magnetic plug and screen for particles AMM 79-21-10-210-002.
     (a) If particles are found:
       1 Inspect alternator stator and rotor for contact, replace as required AMM 73-21-30-000-002 and AMM 73-21-30-400-002.
     (b) If no particles are found:
  • no further maintenance action is required.
   (2) If the failure message ALT, J9, ECU is not confirmed but is repetitive:
  • disconnect the J9 harness from the alternator stator .
     (a) Visually examine the alternator stator receptacle and the J9 harness connector for damaged pins or contamination, and the 90° elbow of the harness boot for evidence of overheat AMM 73-21-50-210-001.
       1 If harness or alternator stator connector is damaged:
  • repair or replace as required.
       2 If no damage is found:
     (b) Visually examine the alternator stator and rotor for evidence of contact.
       1 If evidence of contact is found, the cause must be determined:
  • inspect the alternator rotor nut for proper installation, inspect the AGB lubrication unit magnetic plug and screen for particles AMM 79-21-10-210-002.
         a If chips are found on the chip detector:
         b If rubbing is found and chips were not found on the chip detector:
         c If no rubbing is noted:
     (c) Replace the J9 harness AMM 73-21-50-000-008 and AMM 73-21-50-400-008.
       1 If fault continues during the subsequent flights:
   (3) If the failure message ALT, J9, ECU is confirmed:
  • disconnect the J9 harness from the alternator stator (ALT-A) (located in the left core compartment).
     (a) Visually examine the alternator stator receptacle and the J9 harness connector for damaged pins or contamination AMM 73-21-50-210-001.
       1 If harness or alternator stator connector is damaged:
  • repair or replace as required.
       2 If no damage is found:
  • do an electrical resistance test through the alternator stator connector between:
    . pins 2 and 5 (<1 Ohm)
    . pins 3 and 5 (<1 Ohm)
    . pins 4 and 5 (<1 Ohm)
    . pin 5 and the ground (>10 Megohms).
         a If the resistance values are out of the specified limits:
         b If the resistance values are in the specified limits:
  • reconnect the J9 harness to the alternator stator.
     (b) Disconnect the J9 harness from the ECU (4000KS) receptacle.
     (c) Visually examine the ECU (4000KS) receptacle and the J9 harness connector for damaged pins or contamination AMM 73-21-50-210-001.
       1 If harness connector or ECU receptacle is damaged:
  • repair or replace as required.
       2 If no damage is found:
  • do an electrical resistance test through the J9 harness between:
    . pins 5 and 13 (<1 ohm)
    . pins 5 and 14 (<1 ohm)
    . pins 5 and 15 (<1 ohm)
    . pins 5 and 4 (>10 megohms)
    . pins 13 and 4 (>10 megohms)
    . pins 14 and 4 (>10 megohms)
    . pins 15 and 4 (>10 megohms)
    . pin 5 and the ground (>10 megohms).
         a If the resistance values are out of the specified limits:
         b If the resistance values are in the specified limits:
Subtask 77-10-00-810-091-C ** ON A/C NOT FOR ALL
A. This fault is generated if the ECU detects an open or short circuit on one or more alternator windings and N2 is greater than 58.8% (min idle). This fault is also generated when the FADEC motoring test is active and N2 is less than 15%.
NOTE: A possible cause of the message failure "ALT, J9, ECU" may be the result of a short circuit through J9 wires which can produce an ECU power supply deterioration. The troubleshooting steps must be performed as specified hereunder.
   (1) If the failure message ALT, J9, ECU is not confirmed:
     (a) If particles are found:
       1 Inspect alternator stator and rotor for contact, replace as required AMM 73-21-30-000-001 and AMM 73-21-30-400-001.
     (b) If no particles are found:
  • no further maintenance action is required.
   (2) If the failure message ALT, J9, ECU is not confirmed but is repetitive:
  • disconnect the HJ9 harness from the alternator stator .
     (a) Visually examine the alternator stator receptacle and the HJ9 harness connector for damaged pins or contamination, and the 90° elbow of the harness boot for evidence of overheat AMM 73-21-50-210-002.
       1 If harness or alternator stator connector is damaged:
  • repair or replace as required.
       2 If no damage is found:
     (b) Visually examine the alternator stator and rotor for evidence of contact.
       1 If evidence of contact is found, the cause must be determined:
  • inspect the alternator rotor nut for proper installation, do a check of the Electrical Master Chip Detector for Particles AMM 79-00-00-281-002.
         a If chips are found on the chip detector:
         b If rubbing is found and chips were not found on the chip detector:
         c If no rubbing is noted:
     (c) Replace the HJ9 harness AMM 73-21-50-000-042 and AMM 73-21-50-400-042.
       1 If fault continues during the subsequent flights:
   (3) If the failure message ALT, J9, ECU is confirmed:
  • disconnect the HJ9 harness from the alternator stator (ALT-A) (located in the left core compartment).
     (a) Visually examine the alternator stator receptacle and the HJ9 harness connector for damaged pins or contamination AMM 73-21-50-210-002.
       1 If harness or alternator stator connector is damaged:
  • repair or replace as required.
       2 If no damage is found:
  • do an electrical resistance test through the alternator stator connector between:
    . pins 2 and 5 (<1 Ohm)
    . pins 3 and 5 (<1 Ohm)
    . pins 4 and 5 (<1 Ohm)
    . pin 5 and the ground (>10 Megohms).
         a If the resistance values are out of the specified limits:
         b If the resistance values are in the specified limits:
  • reconnect the HJ9 harness to the alternator stator.
     (b) Disconnect the HJ9 harness from the ECU (4000KS) receptacle.
     (c) Visually examine the ECU (4000KS) receptacle and the HJ9 harness connector for damaged pins or contamination AMM 73-21-50-210-002.
       1 If harness connector or ECU receptacle is damaged:
  • repair or replace as required.
       2 If no damage is found:
  • do an electrical resistance test through the HJ9 harness between:
    . pins 5 and 13 (<1 ohm)
    . pins 5 and 14 (<1 ohm)
    . pins 5 and 15 (<1 ohm)
    . pins 5 and 4 (>10 megohms)
    . pins 13 and 4 (>10 megohms)
    . pins 14 and 4 (>10 megohms)
    . pins 15 and 4 (>10 megohms)
    . pin 5 and the ground (>10 megohms).
         a If the resistance values are out of the specified limits:
         b If the resistance values are in the specified limits:
Subtask 77-10-00-710-125-A ** ON A/C NOT FOR ALL
B. Do the test given in Para. 3.A.
   (1) No additional maintenance action is required if the fault is not confirmed.
   (2) Repeat the fault isolation procedure if the fault continues.
[Rev.8 from Aug 2018] 2026.04.04 04:37:41 UTC
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