Loss of the Channel A of the FADEC on Engine 2 A320
1. Possible Causes:
-ECU (4000KS)
-C/B-ENGINE/2/FADEC A/AND EIU 2 (2KS2)
-EIU-2 (1KS2)
-harness J1
-aircraft wiring
2. Job Set-up Information
A. Referenced Information
| REFERENCE | DESIGNATION |
| Ref. AMM 71-00-00-710-006 | Minimum Idle Check |
| 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. ASM 73-25-08 | |
| 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 73-29-00-710-040 | Operational Test of the FADEC on the ground (with Engine Motoring) |
3. Fault Confirmation
SUBTASK 77-00-00-710-193-B
A. Test
(1) Do the operational test of the FADEC 2A on the ground (with engine motoring) Ref. AMM 73-29-00-710-040.
4.Fault Isolation
SUBTASK 77-00-00-865-059-A
A. Table of the circuit breakers used in this procedure:
| PANEL | DESIGNATION | FIN | LOCATION |
| 49VU | ENGINE/2/FADEC A/AND EIU 2 | 2KS2 | A05 |
| 121VU | ENGINE/ENG2/FADEC B | 4KS2 | Q40 |
SUBTASK 77-00-00-810-150-A
B. If the fault symptom is identified by the upper ECAM warning ENG2 FADEC A FAULT and the test of the FADEC 2A gives no maintenace message:
-disconnect the connector J1 from the ECU (4000KS) and do a check for 28VDC at pin J1/13 with the FADEC GND PWR pushbutton switch released (the ON legend is on).
(1) If there is 28VDC:
-replace the ECU (4000KS) Ref. AMM 73-21-60-000-001 and Ref. AMM 73-21-60-400-001.
(a)If the fault continues:
-do a check for circuit breakers (2KS2) close and (4KS2) open.
(b)If the fault continues:
-replace the C/B-ENGINE/2/FADEC A/AND EIU 2 (2KS2).
(2) If there is no 28VDC:
-do a check for 28VDC at EIU 2 (1KS2) pin AC/11 Ref. ASM 73-25-05.
(a) If there is 28VDC:
-do a check for open or short to ground at the harness J1 between the EIU 2 (1KS2) and the ECU (4000KS), pin AC/7 to pin J1/13. Replace the harness J1 if necessary.
1 If the fault continues:
-make sure that there is no ground signal at EIU 2 (1KS2) pin AA/5B Ref. ASM 73-25-08.
2 If the fault continues:
-replace the EIU-2 (1KS2) Ref. AMM 73-25-34-000-040 and Ref. AMM 73-25-34-400-040.
(b) If there is no 28VDC:
-do a check for open or short to ground at the aircraft wiring between the circuit breaker (2KS2) and EIU 2 (1KS2) pin AC/11.
1 If there is a short to ground:
-repair the above wiring.
2 If there is no short to ground:
-replace the C/B-ENGINE/2/FADEC A/AND EIU 2 (2KS2).
(c) Make sure that 28VDC supplies the ESS bus Ref. ASM 73-25-05.
SUBTASK 77-00-00-710-194-A
C. Do a minimum idle check Ref. AMM 71-00-00-710-006.
