Loss of Data on the ARINC Buses from the two EEC 1 Channels

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1. Possible Causes
· EIU-1 ( 1KS1 )
· EEC ( 4000KS )
· wiring from the EEC 1 to the EIU 1
2 Job Set-up Information
A. Referenced Information
REFERENCE DESIGNATION
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 73-25-06
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 73-22-00-710-050-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 73-22-00-810-050-A
A. If the operational test gives the maintenance message CHECK EEC 1 A1 AND B1 BUS OR EIU 1:
· replace the EIU-1 ( 1KS1 ) , Ref. AMM 73-25-34-000-041 and Ref. AMM 73-25-34-400-041 .
(1) If the fault continues:
· replace the EEC ( 4000KS ) , Ref. AMM 73-22-34-000-010 and Ref. AMM 73-22-34-400-010 .
(2) If the fault continues:
· do a check and repair the:
wiring from the EEC 1 to the EIU 1 pins J1/P, D to pins AA/15A, 15C
wiring from the EEC 1 to the EIU 1 pins J7/P, D to pins AA/14K, 15J Ref. ASM
73-25-06.
Subtask 73-22-00-710-051-A
B. Do the test given in Para. 3. [Rev.6 from Feb 2017] 2026.04.04 04:36:15 UTC