Failure of the ECU Power Supply on Engine 1

TASK 73-25-00-810-843-A
Failure of the ECU Power Supply on Engine 1

1. Possible Causes

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 73-21-60-000-001	Removal of the Electronic Control Unit (ECU)
AMM 73-21-60-400-001	Installation of the Electronic Control Unit (ECU)
ASM 732506
ASM 732510
AMM 73-25-34-000-040	Removal of the Engine Interface Unit (EIU)
AMM 73-25-34-400-040	Installation of the Engine Interface Unit (EIU)
AMM 73-25-34-710-040	Operational Test of the Engine Interface Unit
AMM 73-25-34-710-043	Operational Test of the Engine Interface Unit

3. Fault Confirmation
Subtask 73-25-00-710-132-A ** ON A/C NOT FOR ALL

A. Do the operational test of the Engine Interface Unit (EIU) through the Centralized Fault Display System (CFDS) AMM 73-25-34-710-040.

Subtask 73-25-00-710-132-B ** ON A/C NOT FOR ALL

A. Do the operational test of the Engine Interface Unit (EIU) through the Centralized Fault Display System (CFDS) AMM 73-25-34-710-043.

4. Fault Isolation
Subtask 73-25-00-810-091-A ** ON A/C NOT FOR ALL

A. If the test gives the maintenance message CHECK ECU 1 A1 and B1 BUS or EIU 1:

(1) If the fault continues:

(2) If the fault continues:

do a check and repair the wiring from the ECU 1 (4000KS) to the EIU 1 (1KS1) pins J3/24, 11 to pins AA/15A, 15C and pins J4/24, 11 to pins AA/14K, 14J ASM 732506 and ASM 732510.

Subtask 73-25-00-710-133-A ** ON A/C NOT FOR ALL

B. Do the test given in Para. 3.A.

[Rev.8 from Aug 2018] 2026.04.04 04:35:42 UTC