Failure of ENG/MASTER 1 Control Switch

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1. Possible Causes
· CTL SW-ENG/MASTER 1 ( 3KC )
· EIU-1 ( 1KS1 )
· wiring from the pins A/J, H of the ENG panel (115VU) to the pins AA/5A, 4E of the EIU 1 (1KS1)
· wiring from the pins A/N of the ENG panel (115VU) to the ground
2 Job Set-up Information
A. Referenced Information
REFERENCE DESIGNATION
Ref. ESPM 20-45-21
Ref. AMM 31-10-00-700-001 Test Program after Removal/Installation of a VU panel
Ref. AMM 71-00-00-710-046 Test No.2 : Wet Motor Leak Check
Ref. AWM 73-25-11
Ref. AMM 73-25-34-000-041 Removal of the Engine Interface Unit (EIU)
Ref. AMM 73-25-34-400-041 Installation of the Engine Interface Unit (EIU)
Ref. AMM 73-25-34-710-042 Operational Test of the EIU with the CFDS
3. Fault Confirmation
Subtask 76-12-00-710-050-A
A. Test
(1) Do the operational test of the EIU 1 with the CFDS Ref. AMM 73-25-34-710-042 .
4. Fault Isolation
Subtask 76-12-00-810-050-A
A. If the operational test gives the maintenance message 115VU (MASTER LEVER 1SW):
· remove the 115VU panel.
· replace the CTL SW-ENG/MASTER 1 ( 3KC ) on the panel 115VU Ref. ESPM 20-45-21.
· install the panel 115VU and do a test program after removal/installation of a VU panel Ref.
AMM 31-10-00-700-001 .
· perform a wet motor leak check Ref. AMM 71-00-00-710-046 .
(1) If the fault continues:
· replace the EIU-1 ( 1KS1 ) , Ref. AMM 73-25-34-000-041 and Ref. AMM 73-25-34-400-041 .
(2) If the fault continues:
· do a check and repair the:
wiring from the pins A/J, H of the ENG panel (115VU) to the pins AA/5A, 4E of the
EIU 1 (1KS1) .
wiring from the pins A/N of the ENG panel (115VU) to the ground , Ref. AWM
73-25-11.
Subtask 76-12-00-710-051-A
B. Do the test given in Para. 3. [Rev.6 from Feb 2017] 2026.04.04 04:37:30 UTC