Removal of the Igniter Electrical Lead (131-9(A))

TASK 49-41-43-000-003-A
Removal of the Igniter Electrical Lead (131-9(A))

WARNING: DO NOT TOUCH THE APU UNTIL IT IS SUFFICIENTLY COOL TO PREVENT BURNS WHEN YOU DO THE MAINTENANCE TASK(S).

WARNING: MAKE SURE THAT THE IGNITION UNIT IS DE-ENERGIZED AND GROUNDED BEFORE YOU DISCONNECT THE INPUT AND OUTPUT LEADS. DO NOT TOUCH THE CONTACTS OF THE OUTPUT TERMINAL. THE OUTPUT VOLTAGE FROM THE IGNITION UNIT IS HIGH AND DOES NOT DECREASE IMMEDIATELY AFTER DE-ENERGIZATION (THE UNIT IS OF THE CAPACITOR DISCHARGE TYPE). HIGH VOLTAGE CAN KILL YOU.

1. Reason for the Job
Self explanatory
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	1	ACCESS PLATFORM 4M (13 FT)-ADJUSTABLE
No specific	AR	CAP - BLANKING
No specific	AR	SAFETY CLIP - CIRCUIT BREAKER
No specific	1	WARNING NOTICE(S)

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
315AL, 316AR

C. Referenced Information

REFERENCE	DESIGNATION
TASK 24-42-00-861-001-A	Energize the Ground Service Network from the External Power
TASK 29-00-00-864-001-A	Put the Related Hydraulic System in the Depressurized Configuration before Maintenance Action
TASK 52-41-00-010-001-A	Open the APU Doors for Access
Igniter Lead

3. Job Set-up
Subtask 49-41-43-860-055-A ** ON A/C NOT FOR ALL

A. Aircraft Maintenance Configuration
(1) Energize the ground service network
(Ref. AMM TASK 24-42-00-861-001).
(2) On panel 25VU, make sure that the APU MASTER SW pushbutton switch is in the OFF position, then wait for 7.5 minutes before you do the procedure .
(3) Put a WARNING NOTICE(S) in position in the cockpit to tell persons not to start the APU.
(4) Make sure that the hydraulic systems are depressurized
(Ref. AMM TASK 29-00-00-864-001).

Subtask 49-41-43-865-058-A ** ON A/C NOT FOR ALL

B. Open, safety and tag this(these) circuit breaker(s):

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
121VU	APU/APU/CTL	2KD	L42
121VU	APU/ECB/SPLY	1KD	L41

Subtask 49-41-43-010-053-A ** ON A/C NOT FOR ALL

C. Get Access
(1) Put the ACCESS PLATFORM 4M (13 FT)-ADJUSTABLE in position below APU access doors 315AL and 316AR.
(2) Open APU access doors 315AL 316AR (Ref. AMM TASK 52-41-00-010-001).
(3) Set LIGHT control switch 11LJ to the ON position.

4. Procedure
Subtask 49-41-43-020-052-A ** ON A/C NOT FOR ALL

A. Removal of the Igniter Electrical Lead

WARNING: DISCONNECT THE LOW-TENSION ELECTRICAL SUPPLY 6 MINUTES BEFORE YOU START WORK ON THE IGNITION SYSTEM. THE HIGH CURRENT AND VOLTAGE WHICH ARE USED IN THE IGNITION SYSTEM CAN KILL YOU.

(1) Disconnect low-tension electrical connector (1) and wait for six minutes before you continue.
(2) Disconnect and remove the igniter electrical lead (2) from the igniter plug (3) and the ignition unit (4).
(3) Put the CAP-BLANKING on each disconnected electrical connector and receptacle.

[Rev.10 from 2021] 2026.04.01 01:30:20 UTC