Loss of All Signals from the EIU to the FADEC on Engine 1 Channel A

TASK 71-50-00-810-811-A
Loss of All Signals from the EIU to the FADEC on Engine 1 Channel A

1. Possible Causes

ECU [4000KS]
EIU-1 [1KS1]
C/B-ENGINE/1/FADEC A/AND EIU 1 [2KS1]
C/B-ENGINE/ENG1/FADEC B/AND EIU 1 [4KS1]
harness J3

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)
ASM 732505
ASM 732510
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)

3. Fault Confirmation
Subtask 71-50-00-865-062-A ** ON A/C NOT FOR ALL

A. Table of the circuit breakers used in this procedure:

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
49VU	ENGINE/1/FADEC A/AND EIU 1	2KS1	A04
121VU	ENGINE/ENG1/FADEC B/AND EIU 1	4KS1	R41

Subtask 71-50-00-710-070-A ** ON A/C NOT FOR ALL

B. Do the operational test of the FADEC 1A on the ground (with engine non motoring) AMM 73-29-00-710-040.

4. Fault Isolation
Subtask 71-50-00-810-064-A ** ON A/C NOT FOR ALL

A. If the test gives the maintenance message J3, EIU:

do a visual check of the ECU [4000KS] for integrity ASM 732510.

(1) If the fault continues do a check of the status of circuit breakers 2KS1 and 4KS1 ASM 732505.
(a) If the circuit breakers 2KS1 and 4KS1 are closed:

do a check for 28VDC at EIU 1 pins AC/9, 11.

1 If there is 28VDC:

replace the EIU-1 [1KS1] AMM 73-25-34-000-040 and AMM 73-25-34-400-040.

2 If there is not 28VDC:

do a check of the wiring between the circuit breakers 2KS1 and 4KS1 and the EIU 1 pins AC/9, 11.
if there is no continuity:
repair the wiring.
if there is continuity:
replace the C/B-ENGINE/1/FADEC A/AND EIU 1 [2KS1] and/or C/B-ENGINE/ENG1/FADEC B/AND EIU 1 [4KS1] .

(b) If the circuit breakers 2KS1 and/or 4KS1 are open:

close them.

1 If they trip again:

replace the EIU-1 [1KS1] AMM 73-25-34-000-040 and AMM 73-25-34-400-040.

a If the fault continues:

do a check of the wiring for short to ground between the circuit breakers 2KS1 and/or 4KS1 and the EIU 1.
if the wiring is not correct:
repair it.
if the wiring is correct:
replace the C/B-ENGINE/1/FADEC A/AND EIU 1 [2KS1] and/or C/B-ENGINE/ENG1/FADEC B/AND EIU 1 [4KS1] .

(2) If the fault continues:

replace the harness J3 .

(3) If the fault continues:

replace the ECU [4000KS] AMM 73-21-60-000-001 and AMM 73-21-60-400-001.

Subtask 71-50-00-810-064-B ** ON A/C NOT FOR ALL

A. If the test gives the maintenance message EIU (ARINC), J3:

do a visual check of the ECU [4000KS] for integrity ASM 732510.