Master Lever Fault on EIU-1

TASK 73-25-00-810-A22-A
Master Lever Fault on EIU-1

1. Possible Causes

EIU-1 [1KS1]
CTL SW-ENG/MASTER 1 [3KC]

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AWM 732511
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)
AMM 73-25-34-860-806	Engine Interface Unit (EIU) DISCRETE INPUTS Menu Data Status

3. Fault Confirmation
Subtask 73-25-00-710-459-A ** ON A/C NOT FOR ALL

A. Do the test as follows:
(1) On ENG panel 115VU, make sure that the ENG/MODE/CRANK/AUTO IGN/IGN selector switch (6KS) is in NORM position.
(2) Put the ENG/MASTER 1 control switch (3KC) in ON position.
(3) 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.
(a) Return to CFDS menu.
(4) Put the ENG/MASTER 1 control switch (3KC) in OFF position.
(5) Do the operational test of the EIU with the CFDS to confirm this fault AMM 73-25-34-710-802.
(6) Record the ENG/MASTER 1 control switch position (ON or OFF) that confirms the fault.

4. Fault Isolation
Subtask 73-25-00-810-291-A ** ON A/C NOT FOR ALL

A. If there is confirmation of the fault:
(1) On ENG panel 115VU, make sure that the ENG/MODE/CRANK/AUTO IGN/IGN selector switch (6KS) is in NORM position.
(2) Put the ENG/MASTER 1 control switch (3KC) in position recorded in the Para. 3.A.(6).
(3) Check the status of the EIU-1 discrete input for ENG MASTER SW ON and ENG MASTER SW OFF AMM 73-25-34-860-806.
(4) If the ENG/MASTER 1 control switch (3KC) is in ON position, the status of discrete input:
(a) ENG MASTER SW ON must be equal to 1.
(b) ENG MASTER SW OFF must be equal to 0.
(c) If both statuses are correct:
1 Replace EIU-1 [1KS1] AMM 73-25-34-000-802 and AMM 73-25-34-400-802.
2 Do the test given in Para. 3.
(d) If one status is not correct:
1 Remove EIU-1 [1KS1] AMM 73-25-34-000-802.
2 Remove the ENG/MASTER 1 control switch (3KC).
3 If ENG MASTER SW ON is equal to 0, check wiring between EIU-1 (1KS1) connector AA pin 4E and ENG/MASTER 1 control switch (3KC) pin 2A for continuity AWM 732511.
4 If there is no continuity, repair/replace wiring.
5 If there is continuity:
a Replace CTL SW-ENG/MASTER 1 [3KC] AWM 732511.
6 If ENG MASTER SW OFF is equal to 1, check wiring between EIU-1 (1KS1) connector AA pin 5A and ENG/MASTER 1 control switch (3KC) pin 3A for wire-to-wire short or short to ground AWM 732511.
7 If wiring is not OK, repair/replace wiring.
8 If wiring is OK, replace CTL SW-ENG/MASTER 1 [3KC] AWM 732511.
9 Do the test given in Para. 3.
(5) If the ENG/MASTER 1 control switch (3KC) is in OFF position, the status of discrete input:
(a) ENG MASTER SW ON must be equal to 0.
(b) ENG MASTER SW OFF must be equal to 1.
(c) If both statuses are correct:
1 Replace EIU-1 [1KS1] AMM 73-25-34-000-802 and AMM 73-25-34-400-802.
a Do the test given in Para. 3.
(d) If one status is not correct:
1 Remove EIU-1 [1KS1] AMM 73-25-34-000-802.
2 Remove the ENG/MASTER 1 control switch (3KC).
3 If ENG MASTER SW OFF is equal to 0, check wiring between EIU-1 (1KS1) connector AA pin 5A and ENG/MASTER 1 control switch (3KC) pin 3A for continuity AWM 732511.
4 If there is no continuity, repair/replace wiring.
5 If there is continuity:
a Replace CTL SW-ENG/MASTER 1 [3KC] AWM 732511.
6 If ENG MASTER SW ON is equal to 1, check wiring between EIU-1 (1KS1) connector AA pin 4E and ENG/MASTER 1 control switch (3KC) pin 2A for wire-to-wire short or short to ground AWM 732511.
7 If wiring is not OK, repair/replace wiring.
8 If wiring is OK, replace CTL SW-ENG/MASTER 1 [3KC] AWM 732511.
9 Do the test given in Para. 3.
(6) If the fault continues:
(a) Replace EIU-1 [1KS1] AMM 73-25-34-000-802 and AMM 73-25-34-400-802.
(b) Do the test given in Para. 3.

[Rev.8 from Aug 2018] 2026.04.04 04:36:27 UTC