Uncommanded Continuous Ignition on Engine 1 After Engine Start

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1. Possible Causes
· wiring from the ANTI ICE/ENG 1 pushbutton switch (2DN1) and the EIU-1 (1KS1)
· wiring from the ENG/MODE/CRANK/AUTO IGN/IGN selector switch (6KS) to the EIU-1 (1KS1)
· EIU-1 ( 1KS1 )
2 Job Set-up Information
A. Referenced Information
REFERENCE DESIGNATION
Ref. ASM 73-25-08
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)
3. Fault Confirmation
Subtask 74-00-00-710-096-A
A. Test
(1) Not applicable, the fault is evident.
4. Fault Isolation
Subtask 74-00-00-810-074-B
A. If the fault symptom is identified by the crew observation ENG 1 - Uncommanded continuous IGNITION
after engine start:
· do a check of the wiring from the ANTI ICE/ENG 1 pushbutton switch (2DN1) and the EIU-1 (1KS1)
. pin AA/B2 to pin AA/5C Ref. ASM 73-25-08.
(1) If the fault continues:
· do a check of the wiring from the ENG/MODE/CRANK/AUTO IGN/IGN selector switch (6KS) to the
EIU-1 (1KS1)
. pin 3 to pin AA/1A
. pin 4 to pin AA/1B Ref. ASM 73-25-08.
(2) If the fault continues:
· replace the EIU-1 ( 1KS1 ) Ref. AMM 73-25-34-000-041 and Ref. AMM 73-25-34-400-041 .
Subtask 74-00-00-710-097-A
B. After the subsequent flight, make sure that the fault does not continue. [Rev.6 from Feb 2017] 2026.04.04 04:36:59 UTC