Failure of the IDG 1 Servo Valve or its Wiring

TASK 24-20-00-810-876-A
Failure of the IDG 1 Servo Valve or its Wiring

1. Possible Causes

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 24-41-00-740-002	Operational Check of the GAPCU via the CFDS
AMM 24-41-00-861-002	Energize the Aircraft Electrical Circuits from the External Power
AMM 24-41-00-862-002	De-energize the Aircraft Electrical Circuits Supplied from the External Power
AMM 31-60-00-860-001	EIS Start Procedure
AMM 31-60-00-860-002	EIS Stop Procedure
AMM 71-00-00-860-814	Shutdown of the Engine
AMM 71-00-00-860-823	Start the Engine (Normal Automatic Start)

3. Fault Isolation

CAUTION: BEFORE YOU START THE CHECK OF IDG WIRING THAT INCLUDES CONNECTORS, EXAMINE EACH CONNECTOR TO MAKE SURE THAT THERE IS NO CONTAMINATION IN IT. IF YOU FIND CONTAMINATION, CLEAN THE CONNECTOR AND CONNECT IT AGAIN. IF THE FAILURE CONTINUES, DO THE TROUBLE SHOOTING PROCEDURE AS GIVEN BELOW.

Subtask 24-20-00-710-103-C ** ON A/C NOT FOR ALL

A. Do this operational test to make sure that the system operates correctly.
(1) Aircraft Maintenance Configuration
(a) Energize the aircraft electrical circuits
AMM 24-41-00-861-002.
(b) Do the EIS start procedure (Upper ECAM DU and lower ECAM DU only)
AMM 31-60-00-860-001.
(2) In the cockpit, on the ELEC panel 35VU:

Push, release and push again the GEN 1 pushbutton switch (3XU1).

(3) Do the BITE test of the GAPCU AMM 24-41-00-740-002.
(4) Start engine 1 AMM 71-00-00-860-823.
(5) Do this test:

ACTION	RESULT
On the ECAM control panel: Push the ELEC key to get the ELEC page.	On the lower ECAM DU: The correct electrical parameters of GEN 1 are shown and GEN 1 supplies the AC1 busbar.

4. Close-up
Subtask 24-20-00-860-130-E ** ON A/C NOT FOR ALL

A. Put the aircraft back to its initial configuration.
(1) Stop engine 1 AMM 71-00-00-860-814.
(2) Do the EIS stop procedure
AMM 31-60-00-860-002.
(3) On the ECAM control panel, set the UPPER DISPLAY and LOWER DISPLAY potentiometers to OFF.
(4) De-energize the aircraft electrical circuits
AMM 24-41-00-862-002.

[Rev.8 from Aug 2018] 2026.04.04 04:26:17 UTC