W DOC AIRBUS | TSM A320F

Loss of the ECU Cross Channel on Engine 2 - Channel A

TASK 77-10-00-810-848-A
Loss of the ECU Cross Channel on Engine 2 - Channel A

1. Possible Causes
  • Alternator Stator
  • Accessory Gearbox Module
  • Alternator Rotor
  • J9 Harness
  • ECU [4000KS]
  • Accessory Gearbox Assembly
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 77-10-00-710-140-A ** ON A/C NOT FOR ALL
A. Do the operational test of the FADEC 2B on the ground (with engine non motoring) AMM 73-29-00-710-040.
4. Fault Isolation
Subtask 77-10-00-810-103-A ** ON A/C NOT FOR ALL
A. If the failure message ECU (B CHANNEL) is not confirmed:
  • no maintenance action is required.
NOTE: This failure message is generated when there is an internal ECU cross channel fault, control alternator stator contact, or related wiring.
Subtask 77-10-00-810-116-A ** ON A/C NOT FOR ALL
B. If the failure message ECU (B CHANNEL) is not confirmed but is repetitive:
  • do a check of the J9 harness connection at the control alternator:
   (1) If the connection is loose:
  • tighten the connection by hand plus one eighth of a turn.
NOTE: Soft nose pliers may be used if necessary.
   (2) If the connection is tight:
  • 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:
  • remove the Alternator Stator AMM 73-21-30-000-002.
  • visually examine the alternator stator and rotor for evidence of contact.
         a If evidence of contact is found, the cause must be determined:
         b If no evidence of contact is found:
   (3) If fault continues during the subsequent flights:
Subtask 77-10-00-810-117-A ** ON A/C NOT FOR ALL
C. If the failure message ECU (B CHANNEL) is confirmed:
  • do a check of the J9 harness connection at the control alternator:
   (1) If the connection is loose:
  • tighten the connection by hand plus one eighth of a turn.
NOTE: Soft nose pliers may be used if necessary.
   (2) If the connection is tight:
  • disconnect the J9 harness from the alternator stator (ALT-B) (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)
    . pins 5 and the ground (>10 Megohms)
       3 If the resistance values are out of the specified limits:
       4 If the resistance values are in the specified limits:
  • reconnect the J9 harness to the alternator stator.
  • disconnect the J9 harness from the ECU (4000KS) receptacle.
  • Visually examine the ECU (4000KS) receptacle and the J9 harness connector for damaged pins or contamination AMM 73-21-50-210-001.
         a If harness connector or ECU receptacle is damaged:
  • repair or replace as required.
         b 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)

    * If the resistance values are out of the specified limits:
    - replace the J9 harness AMM 73-21-50-000-008 and AMM 73-21-50-400-008.

    * If the resistance values are in the specified limits:
    - replace the ECU (4000KS) AMM 73-21-60-000-001 and AMM 73-21-60-400-001.
Subtask 77-10-00-810-116-B ** ON A/C NOT FOR ALL
D. If the failure message ECU (B CHANNEL) is not confirmed but is repetitive:
  • do a check of the J9 harness connection at the control alternator:
   (1) If the connection is loose:
  • tighten the connection by hand plus one eighth of a turn.
NOTE: Soft nose pliers may be used if necessary.
   (2) If the connection is tight:
  • 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 73-21-50-210-002.
       1 If harness or alternator stator connector is damaged:
  • repair or replace as required.
       2 If no damage is found:
  • remove the Alternator Stator AMM 73-21-30-000-001.
  • visually examine the alternator stator and rotor for evidence of contact.
         a If evidence of contact is found, the cause must be determined:
         b If no evidence of contact is found:
   (3) If fault continues during the subsequent flights:
Subtask 77-10-00-810-117-B ** ON A/C NOT FOR ALL
E. If the failure message ECU (B CHANNEL) is confirmed:
  • do a check of the J9 harness connection at the control alternator:
   (1) If the connection is loose:
  • tighten the connection by hand plus one eighth of a turn.
NOTE: Soft nose pliers may be used if necessary.
   (2) If the connection is tight:
  • disconnect the J9 harness from the alternator stator (ALT-B) (located in the left core compartment).
     (a) Visually examine the alternator stator receptacle and the J9 harness connector for damaged pins or contamination AMM 73-21-50-210-002.
       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)
    . pins 5 and the ground (>10 Megohms)
       3 If the resistance values are out of the specified limits:
       4 If the resistance values are in the specified limits:
  • reconnect the J9 harness to the alternator stator.
  • disconnect the J9 harness from the ECU (4000KS) receptacle.
  • Visually examine the ECU (4000KS) receptacle and the J9 harness connector for damaged pins or contamination AMM 73-21-50-210-002.
         a If harness connector or ECU receptacle is damaged:
  • repair or replace as required.
         b 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)

    * If the resistance values are out of the specified limits:
    - replace the J9 harness AMM 73-21-50-000-042 and AMM 73-21-50-400-042.

    * If the resistance values are in the specified limits:
    - replace the ECU (4000KS) AMM 73-21-60-000-001 and AMM 73-21-60-400-001.
Subtask 77-10-00-710-151-A ** ON A/C NOT FOR ALL
F. 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 04:37:42 UTC
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