EIU-2 Fault to Supply EEC A and B

TASK 73-25-00-810-A27-A
EIU-2 Fault to Supply EEC A and B

1. Possible Causes

EIU-2 [1KS2]
HARNESS-FAN, WF02 [4218KS]
HARNESS-FAN, WF01 [4217KS]

2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	AR	SAFETY CLIP - CIRCUIT BREAKER

B. Referenced Information

REFERENCE	DESIGNATION
AMM 73-21-61-000-802	Removal of the Electronic Engine Control (EEC) Wiring Harness (WF01)
AMM 73-21-61-400-802	Installation of the Electronic Engine Control (EEC) Wiring Harness (WF01)
AMM 73-21-62-000-802	Removal of the EEC Wiring Harness (WF02)
AMM 73-21-62-400-802	Installation of the EEC Wiring Harness (WF02)
AWM 732504
AMM 73-25-34-000-802	Removal of the Engine Interface Unit (EIU)
AMM 73-25-34-400-802	Installation of the Engine Interface Unit (EIU)
AMM 73-25-34-710-802	Operational Test of the Engine Interface Unit (EIU) with the Centralized Fault Display System (CFDS)

3. Fault Confirmation
Subtask 73-25-00-710-464-A ** ON A/C NOT FOR ALL

A. Do the operational test of the Engine Interface Unit (EIU) with the Centralized Fault Display System (CFDS) to confirm this fault AMM 73-25-34-710-802.

4. Fault Isolation
Subtask 73-25-00-810-297-A ** ON A/C NOT FOR ALL

A. If there is confirmation of the fault:
(1) Replace EIU-2 [1KS2] AMM 73-25-34-000-802 and AMM 73-25-34-400-802.
(2) Do the test given in Para. 3.
(3) If the fault continues:
(a) Troubleshoot as follows.

Subtask 73-25-00-865-076-A ** ON A/C NOT FOR ALL

B. Open, safety and tag this(these) circuit breaker(s):

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
FOR FIN: 4020KM2 (POWER PLANTDEMOUNTABLE, ENG 2)
49VU	ENGINE/2/FADEC A/AND EIU 2	2KS2	A05
121VU	ENGINE/ENG2/FADEC B/AND EIU 2	4KS2	Q40

Subtask 73-25-00-810-298-A ** ON A/C NOT FOR ALL

C. Check for harness fault.
(1) Disconnect connectors (P402) and (P403) and check for 28 VDC at pin 21 of both connectors (402VC2) and (403VC2).
(2) If there is 28 VDC at pin 21 of connector (402VC2):
(a) Repair/replace aircraft wiring AWM 732504.
(b) Do the test given in Para. 3.
(3) If there is not 28 VDC:
(a) Replace HARNESS-FAN, WF02 [4218KS] AMM 73-21-62-000-802 and AMM 73-21-62-400-802.
(b) Do the test given in Para. 3.
(4) If there is 28 VDC at pin 21 of connector (403VC2):
(a) Repair/replace aircraft wiring AWM 732504.
(b) Do the test given in Para. 3.
(5) If there is not 28 VDC:
(a) Replace HARNESS-FAN, WF01 [4217KS] AMM 73-21-61-000-802 and AMM 73-21-61-400-802.
(b) Do the test given in Para. 3.
(6) Connect connectors (P402) and (P403) if necessary.

5. Close-up
Subtask 73-25-00-865-077-A ** ON A/C NOT FOR ALL

A. Remove the safety clip(s) and the tag(s) and close this(these) circuit breaker(s):

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
FOR FIN: 4020KM2 (POWER PLANTDEMOUNTABLE, ENG 2)
49VU	ENGINE/2/FADEC A/AND EIU 2	2KS2	A05
121VU	ENGINE/ENG2/FADEC B/AND EIU 2	4KS2	Q40

[Rev.8 from Aug 2018] 2026.04.04 04:36:28 UTC