Loss of Data on the ARINC Bus from the EIU to the FADEC on Engine 1

TASK 73-25-00-810-897-A
Loss of Data on the ARINC Bus from the EIU to the FADEC on Engine 1

1. Possible Causes

EIU-1 [1KS1]
ECU [4000KS]

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)

3. Fault Confirmation
Subtask 73-25-00-710-242-A ** ON A/C NOT FOR ALL

A. 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 73-25-00-810-148-A ** ON A/C NOT FOR ALL

A. If the test gives the maintenance message EIU (031), J3:

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

(1) If the fault continues:

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

Subtask 73-25-00-710-243-A ** ON A/C NOT FOR ALL

B. Do the test given in Para. 3.A.
(1) No additional maintenance action is required if the fault is not confirmed.
(2) Repeat the fault isolation procedure if the fault continues.

[Rev.8 from Aug 2018] 2026.04.04 04:35:47 UTC