Failure of the EIU on Engine 1 A320
1. Possible Causes:
-EIU-1 (1KS1)
-C/B-ENGINE/1/FADEC A/AND EIU 1 (2KS1)
-C/B-ENGINE/ENG1/FADEC B/AND EIU 1 (4KS1)
-ECU (4000KS)
-aircraft wirings
2. Job Set-up Information
A. Referenced Information
| REFERENCE | DESIGNATION |
| Ref. AMM 73-21-60-000-001 | Removal of the Electronic Control Unit (ECU) |
| Ref. AMM 73-21-60-400-001 | Installation of the Electronic Control Unit (ECU) |
| Ref. ASM 73-25-05 | |
| Ref. AMM 73-25-34-000-040 | Removal of the Engine Interface Unit (EIU) |
| Ref. AMM 73-25-34-400-040 | Installation of the Engine Interface Unit (EIU) |
| Ref. AMM 73-25-34-710-043 | Operational Test of the Engine Interface Unit |
3. Fault Confirmation
SUBTASK 73-25-00-710-154-B
A. Do the operational test of the Engine Interface Unit (EIU) through the Centralized Fault Display System (CFDS) Ref. AMM 73-25-34-710-043.
4. Fault Isolation
SUBTASK 73-25-00-865-056-A
A. Table of the circuit breakers used in this procedure:
| 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 73-25-00-810-102-A
B. If the test gives the maintenance message EIU 1:
-do a check for 28VDC at EIU 1 (1KS1) pins AC/9, 11.
(1) if there is 28VDC:
-replace the EIU-1 (1KS1) Ref. AMM 73-25-34-000-040 and Ref. AMM 73-25-34-400-040.
(2) If there is no 28VDC:
-do a check for open or short to ground of the aircraft wirings between the EIU 1 (1KS1) and the circuit breakers (2KS1) and (4KS1) pins AC/9, 11.
(a) If there is a short to ground:
-repair the defective wiring(s)
(b) If there is no a short to ground:
-replace the defective C/B-ENGINE/1/FADEC A/AND EIU 1 (2KS1) or the C/B-ENGINE/ENG1/FADEC B/AND EIU 1 (4KS1) Ref. ASM 73-25-05.
(3) If the fault continues:
-replace the ECU (4000KS) Ref. AMM 73-21-60-000-001 and Ref. AMM 73-21-60-400-001.
SUBTASK 73-25-00-710-155-B
C. Do the operational test of the Engine Interface Unit (EIU) through the Centralized Fault Display System (CFDS) Ref. AMM 73-25-34-710-043.
