Loss of Data on the ARINC Bus from the EIU to the FADEC on Engine 2

TASK 73-25-00-810-894-A
Loss of Data on the ARINC Bus from the EIU to the FADEC on Engine 2

1. Possible Causes

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 21-61-34-000-002	Removal of the Air-Conditioning System Controller
AMM 21-61-34-400-002	Installation of the Air-Conditioning System Controller
AMM 21-63-34-000-001	Removal of the Zone Controller
AMM 21-63-34-400-001	Installation of the Zone Controller
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 732506
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)

3. Fault Confirmation
Subtask 73-25-00-710-236-A ** ON A/C NOT FOR ALL

A. Test
(1) Not applicable.

4. Fault Isolation
Subtask 73-25-00-810-145-A ** ON A/C NOT FOR ALL

A. Replace the ZONE CONTROLLER [8HK] AMM 21-63-34-000-001 and AMM 21-63-34-400-001.
(1) If the fault continues:

Do a check for open or short to ground of the between the EIU (1KS2) and harness J3 the ECU (4000KS) pins AB/5A, 5C to pins J3/22, 23 ASM 732506

(a) If the wiring is not correct:

(b) If the wiring is correct:

Subtask 73-25-00-810-145-B ** ON A/C NOT FOR ALL

A. Replace the CONT-AIR COND SYSTEM 1 [47HH] and CONT-AIR COND SYSTEM 2 [57HH] AMM 21-61-34-000-002 and AMM 21-61-34-400-002.
(1) If the fault continues:

Do a check for open or short to ground of the between the EIU (1KS2) and harness J3 the ECU (4000KS) pins AB/5A, 5C to pins J3/22, 23 ASM 732506

(a) If the wiring is not correct:

(b) If the wiring is correct:

Subtask 73-25-00-710-237-A ** ON A/C NOT FOR ALL

B. No additionnal maintenance action is required if the fault is not confirmed.
(1) Repeat the fault isolation procedure if the fault continues.

[Rev.8 from Aug 2018] 2026.04.04 04:35:46 UTC