Loss of the Output 2 Bus on EEC 1 Channel B

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1. Possible Causes
· EEC ( 4000KS )
· wiring of EEC B OUTPUT 2 signal from the EEC 1 (4000KS) to the first terminal block
2 Job Set-up Information
A. Referenced Information
REFERENCE DESIGNATION
Ref. AMM 31-60-00-740-002 Perform Electronic Instrument System (EIS) Input Test
Ref. AMM 31-60-00-740-007 GROUND SCANNING Test of the DMC
Ref. AMM 73-22-34-000-010 Removal of the Electronic Engine Control (EEC)
Ref. AMM 73-22-34-400-010 Installation of the Electronic Engine Control (EEC)
Ref. ASM 73-25-10
3. Fault Confirmation
Subtask 73-20-00-740-070-A
A. Test
(1) Do the EIS input test Ref. AMM 31-60-00-740-002 .
Subtask 73-20-00-740-070-B
A. Test
(1) Do the EIS input test Ref. AMM 31-60-00-740-007 .
4. Fault Isolation
Subtask 73-20-00-810-076-A
A. If the test gives the maintenance message DMC3 : NO EEC 1B DATA:
· replace the EEC ( 4000KS ) , Ref. AMM 73-22-34-000-010 and Ref. AMM 73-22-34-400-010 .
(1) If the fault continues:
· do a check and repair the wiring of EEC B OUTPUT 2 signal from the EEC 1 (4000KS) to the first
terminal block , Ref. ASM 73-25-10.
Subtask 73-20-00-810-076-B
A. If the test gives the maintenance message: EEC(E1-4000KS)BUS EEC 1A/DMC3(1WT3)
· replace the EEC ( 4000KS ) , Ref. AMM 73-22-34-000-010 and Ref. AMM 73-22-34-400-010 .
(1) If the fault continues:
· do a check and repair the wiring of EEC B OUTPUT 2 signal from the EEC 1 (4000KS) to the first
terminal block , Ref. ASM 73-25-10.
Subtask 73-20-00-740-071-A
B. Do the test given in Para. 3. [Rev.6 from Feb 2017] 2026.04.04 04:36:12 UTC