EIU-1 Relay Fault for Hydraulic Pump Depressurization

TASK 73-25-00-810-A50-A
EIU-1 Relay Fault for Hydraulic Pump Depressurization

1. Possible Causes

EIU-1 [1KS1]
PUMP VARIABLE DTS [1030GK]
HARNESS-IDG, ENG PUMP AND LOW OIL PRESS SW [4155KS]
aircraft wiring

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AWM 291101
AMM 29-11-51-000-805	Removal of the Green Engine Driven Pump
AMM 29-11-51-400-805	Installation of the Green Engine Driven Pump
AMM 71-13-00-410-802	Closing of the Fan Cowl Doors
AMM 71-51-40-000-801	Removal of the IDG-EDP-MON Harness
AMM 71-51-40-400-801	Installation of the IDG-EDP-MON Harness
AMM 73-25-34-000-802	Removal of the Engine Interface Unit (EIU)
AMM 73-25-34-400-802	Installation of the Engine Interface Unit (EIU)
AMM 73-25-34-710-802	Operational Test of the Engine Interface Unit (EIU) with the Centralized Fault Display System (CFDS)
AMM 78-36-00-010-802	Opening of the Thrust Reverser Cowl-Doors

3. Fault Confirmation
Subtask 73-25-00-710-487-A ** ON A/C NOT FOR ALL

A. Do the operational test of the Engine Interface Unit (EIU) with the Centralized Fault Display System (CFDS) to confirm this fault AMM 73-25-34-710-802.

4. Fault Isolation
Subtask 73-25-00-810-331-A ** ON A/C NOT FOR ALL

A. If there is confirmation of the fault:
(1) Replace EIU-1 [1KS1] AMM 73-25-34-000-802 and AMM 73-25-34-400-802.
(a) Do the test given in Para. 3.
(2) If the fault continues:
(a) On HYD/Fuel panel 40VU, make sure that the pushbutton switch (1705GK) is released (OFF legend is off).
(3) Remove EIU-1 [1KS1] AMM 73-25-34-000-802.
(4) Open the right thrust reverser cowl-door AMM 78-36-00-010-802.
(5) Remove connector (1030GK-A) from the hydraulic engine pump.
(6) Put a shunt between pins 1 and 3 of connector (1030GK-A)
(7) On shelf 85VU, check for a ground at pin 15J of connector AB at rack side.
(a) If you find a ground:
1 Replace PUMP VARIABLE DTS [1030GK] AMM 29-11-51-000-805 and AMM 29-11-51-400-805.
2 Do the test given in Para. 3.
(8) If you do not find a ground:
(a) Remove the shunt.
(b) Remove connector (404VC1-A) from the pylon junction box.
(c) Examine the pins and sockets (contacts) for alignment and damage. Look for contacts pushed rearward into both connectors face. Replace parts as necessary.
(d) If you find damage:
1 Do the test given in Para. 3.
(9) If you find no damage to connectors or if the fault continues, put a shunt between pins 22 and 23 of connector (404VC1).
(10) On shelf 85VU, check for a ground at pin 15J of connector AB at rack side.
(a) Remove the shunt.
(b) If you find a ground:
1 Replace HARNESS-IDG, ENG PUMP AND LOW OIL PRESS SW [4155KS] AMM 71-51-40-000-801 and AMM 71-51-40-400-801.
2 Do the test given in Para. 3.
(11) If you do not find a ground:
(a) Repair or replace aircraft wiring AWM 291101.
(b) Do the test given in Para. 3.

5. Close-up
Subtask 73-25-00-860-092-A ** ON A/C NOT FOR ALL

A. Put the aircraft back to its initial configuration.
(1) Make sure that the work area is clean and clear of tools and other items.
(a) Close the fan cowl doors AMM 71-13-00-410-802.

[Rev.8 from Aug 2018] 2026.04.04 04:36:29 UTC