W DOC AIRBUS | TSM A320F

Loss of the 115VAC Power Supply on the ECU 2

TASK 71-50-00-810-802-A
Loss of the 115VAC Power Supply on the ECU 2

1. Possible Causes
  • ECU [4000KS]
  • EIU-2 [1KS2]
  • J1 harness
  • wiring
  • C/B-ENGINE/1 AND 2/IGN/SYS A [1JH]
2. Job Set-up Information
 A. Referenced Information
REFERENCE
DESIGNATION
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 73-25-34-000-040
Removal of the Engine Interface Unit (EIU)
AMM 73-25-34-400-040
Installation of the Engine Interface Unit (EIU)
AMM 73-29-00-710-040
Operational Test of the FADEC on the ground (with Engine Motoring)
ASM 743101
3. Fault Confirmation
Subtask 71-50-00-865-052-A ** ON A/C NOT FOR ALL
A. Make sure that this(these) circuit breaker(s) is(are) closed:
PANELDESIGNATIONFINLOCATION
** ON A/C NOT FOR ALL
49VUENGINE/1 AND 2/IGN/SYS A1JHA03
Subtask 71-50-00-710-052-A ** ON A/C NOT FOR ALL
B. Test
   (1) If you cannot close the circuit breaker (1JH), refer to Para. 4.B.
   (2) Do the operational test of the FADEC 2A on the ground (with engine non motoring) AMM 73-29-00-710-040
4. Fault Isolation
Subtask 71-50-00-810-052-A ** ON A/C NOT FOR ALL
CAUTION: WHEN THE "ENG/MASTER" LEVER IS IN THE "ON" POSITION, BE VERY CAREFUL NOT TO SET THE "ENG/MODE" SELECTOR SWITCH TO "CRANK" OR "IGN/START". IF YOU SET THE SELECTOR SWITCH TO ONE OF THESE POSITIONS, THE ENGINE WILL START. THERE IS THUS A RISK OF INJURY TO PERSONS AND OF DAMAGE TO EQUIPMENT.
A. If the circuit breaker (1JH) is closed and if the test gives the maintenance message J1, 115 VOLTS AC:
  • On the panel 115 VU, set the MASTER switch to "ON".
  • do a check for 115VAC at the ECU (4000KS) pins J1/7 ASM 743101.
  • On the panel 115 VU, set the MASTER switch to "OFF".
   (1) If there is 115VAC:
   (2) If there is no 115VAC:
  • do a check for 115VAC at the EIU-2 (1KS2) pin AB/14F.
     (a) If there is 115VAC:
       1 If the fault continues:
  • replace the J1 harness between the EIU-2 (1KS2) and the ECU (4000KS).
     (b) If there is no 115VAC:
  • do a check of the wiring between the EIU-2 (1KS2) pin AB/14F and the circuit breaker (1JH).
       1 If there is no continuity:
  • repair the above wiring.
       2 If there is continuity:
  • replace the C/B-ENGINE/1 AND 2/IGN/SYS A [1JH] .
   (3) If the fault continues:
  • make sure that there is no ground signal at the EIU-2 (1KS2) pin AA/5B.
Subtask 71-50-00-810-052-B ** ON A/C NOT FOR ALL
CAUTION: WHEN THE "ENG/MASTER" LEVER IS IN THE "ON" POSITION, BE VERY CAREFUL NOT TO SET THE "ENG/MODE" SELECTOR SWITCH TO "CRANK" OR "IGN/START". IF YOU SET THE SELECTOR SWITCH TO ONE OF THESE POSITIONS, THE ENGINE WILL START. THERE IS THUS A RISK OF INJURY TO PERSONS AND OF DAMAGE TO EQUIPMENT.
A. If the circuit breaker (1JH) is closed and if the test gives the maintenance message J1, 115 VAC, ECU:
  • On the panel 115 VU, set the MASTER switch to "ON".
  • do a check for 115VAC at the ECU (4000KS) pins J1/7 ASM 743101.
  • On the panel 115 VU, set the MASTER switch to "OFF".
   (1) If there is 115VAC:
   (2) If there is no 115VAC:
  • do a check for 115VAC at the EIU-2 (1KS2) pin AB/14F.
     (a) If there is 115VAC:
       1 If the fault continues:
  • replace the J1 harness between the EIU-2 (1KS2) and the ECU (4000KS).
     (b) If there is no 115VAC:
  • do a check of the wiring between the EIU-2 (1KS2) pin AB/14F and the circuit breaker (1JH).
       1 If there is no continuity:
  • repair the above wiring.
       2 If there is continuity:
  • replace the C/B-ENGINE/1 AND 2/IGN/SYS A [1JH] .
   (3) If the fault continues:
  • make sure that there is no ground signal at the EIU-2 (1KS2) pin AA/5B.
Subtask 71-50-00-810-053-A ** ON A/C NOT FOR ALL
B. If the circuit breaker (1JH) is open:
  • close it.
   (1) If the circuit breaker trips:
   (2) If the circuit breaker trips again:
  • do a check and repair the wiring for short to ground between the EIU-2 (1KS2) pin AB/14F and the circuit breaker (1JH).
     (a) If the fault continues:
  • replace the C/B-ENGINE/1 AND 2/IGN/SYS A [1JH] .
   (3) If the circuit breaker stays closed:
     (a) If the circuit breaker trips:
     (b) If the circuit breaker stays closed:
       1 If the circuit breaker trips:
       2 If the circuit breaker trips again:
  • do a check and repair the wiring between the ECU (4000KS) pins J1/7 and the EIU-2 (1KS2) pin AB/14B.
   (4) If the fault continues:
  • make sure that there is no ground signal at the EIU-2 (1KS2) pin AA/5B.
Subtask 71-50-00-710-053-A ** ON A/C NOT FOR ALL
C. Do the test given in Para. 3.
[Rev.8 from Aug 2018] 2026.04.04 04:34:57 UTC
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