DOC AIRBUS | TSM A320FFailure of the EIU 1 Circuit
1. Possible Causes
· EIU-1 ( 1KS1 )
· wiring from the circuit breaker 4KS1 to the EIU-1 (1KS1) pin AC/9
· wiring from the circuit breaker 2KS1 to the EIU-1 (1KS1) pin AC/11
· wiring from the EIU-1 (1KS1) to the EEC-1 (4000KS)
· EEC ( 4000KS )
2 Job Set-up Information
A. Referenced Information
REFERENCE DESIGNATION
Ref. AMM 71-00-00-710-012 Test No.3 : Idle Leak Check
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 73-25-05
Ref. ASM 73-25-06
Ref. AMM 73-25-34-000-041 Removal of the Engine Interface Unit (EIU)
Ref. AMM 73-25-34-400-041 Installation of the Engine Interface Unit (EIU)
Ref. AMM 73-25-34-710-042 Operational Test of the EIU with the CFDS
3. Fault Confirmation
Subtask 73-25-00-865-050-A
A. Make sure that this(these) circuit breaker(s) is(are) closed:
PANEL DESIGNATION FIN LOCATION
49VU ENGINE/1/FADEC A/AND EIU 1 2KS1 A04
121VU ENGINE/ENG1/FADEC B/AND EIU 1 4KS1 R41
Subtask 73-25-00-710-222-A
B. Test
(1) Do the operational test of the EIU 1 with the CFDS Ref. AMM 73-25-34-710-042 .
(2) Do the operational test of the FADEC SYSTEM (FADEC 1A and FADEC 1B) on the ground Ref.
AMM 73-22-00-710-040 .
4. Fault Isolation
Subtask 73-25-00-810-136-A
A. If the test gives a maintenance message, do the applicable trouble shooting procedure
NOTE: Before you do the troubleshooting procedure of the EIU 1, make sure that, on the Post Flight Report
(PFR), no ATA 24 fault occurred at the same time as the EIU fault. This is because a power
supply interruption (ATA 24) can cause an EIU fault.
Subtask 73-25-00-810-137-A
B. If the test gives no maintenance message:
(1) Remove the EIU-1 (1KS1) Ref. AMM 73-25-34-000-041 .
(2) Do a visual inspection of connectors at 85VU side.
(a) Repair connector if necessary.
(3) Do a visual inspection of connectors at EIU-1 (1KS1) side.
(a) If damage is found:
· Replace the EIU-1 ( 1KS1 ) Ref. AMM 73-25-34-000-041 and Ref. AMM 73-25-34-400-041 .
(b) If no damage is found:
· Do a check of the:
. wiring from the circuit breaker 4KS1 to the EIU-1 (1KS1) pin AC/9
. wiring from the circuit breaker 2KS1 to the EIU-1 (1KS1) pin AC/11 Ref.
ASM 73-25-05.
1 If there is no continuity:
· Repair the above wiring.
2 If there is continuity:
· Do a check of the:
. wiring from the EIU-1 (1KS1) to the EEC-1 (4000KS) pins
AB/5A, 5C to pins J1/P, N
. wiring from the EIU-1 (1KS1) to the EEC-1 (4000KS) pins
AB/5A, 5C to pins J7/P, N Ref. ASM 73-25-06.
a If there is no continuity:
· Repair the above wiring.
b If there is continuity:
· Replace the EIU-1 ( 1KS1 ) Ref. AMM 73-25-34-000-041 and Ref.
AMM 73-25-34-400-041 .
(4) If the fault persist:
· Replace the EEC ( 4000KS ) Ref. AMM 73-22-34-000-010 and Ref. AMM 73-22-34-400-010 .
Subtask 73-25-00-710-223-A
C. Do the idle leak check Ref. AMM 71-00-00-710-012 and make sure that the ENG 1 EIU FAULT warning
does not come into view on the upper ECAM display unit. [Rev.6 from Feb 2017] 2026.04.04 04:36:24 UTC