Loss of the Output B Bus on EIU 1

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1. Possible Causes
· EIU-1 ( 1KS1 )
· wiring from the EIU 1 (1KS1) pins AB/5H, 5K to the first terminal block
2 Job Set-up Information
A. Referenced Information
REFERENCE DESIGNATION
Ref. AMM 31-32-00-869-002 Procedure for Class 3 Faults Reading
Ref. ASM 73-25-06
Ref. AMM 73-25-34-000-041 Removal of the Engine Interface Unit (EIU)
REFERENCE DESIGNATION
Ref. AMM 73-25-34-400-041 Installation of the Engine Interface Unit (EIU)
3. Fault Confirmation
Subtask 73-20-00-865-052-A
A. Make sure that this(these) circuit breaker(s) is(are) closed:
PANEL DESIGNATION FIN LOCATION
49VU ENGINE/1/FADEC A/AND EIU 1 2KS1 A04
121VU ENGINE/ENG1/FADEC B/AND EIU 1 4KS1 R41
Subtask 73-20-00-710-090-A
B. Test
(1) On the CFDS MENU page, get access to the AVIONICS STATUS page Ref.
AMM 31-32-00-869-002 .
4. Fault Isolation
Subtask 73-20-00-810-084-A
A. If the test gives the maintenance message NO EIU1 DATA:
· 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:
· do a check and repair the wiring from the EIU 1 (1KS1) pins AB/5H, 5K to the first terminal block ,
Ref. ASM 73-25-06.
Subtask 73-20-00-710-091-A
B. Do the test given in Para. 3. [Rev.6 from Feb 2017] 2026.04.04 04:36:13 UTC