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

TASK 49-41-43-400-003-A
Installation 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	1	WARNING NOTICE(S)
No specific	Torque wrench: range to between 2.66 and 2.42 m.daN (19.62 and 17.85 lbf.ft )

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 24-42-00-862-001-A	De-energize the Ground Service Network Supplied from the External Power
TASK 29-00-00-864-001-A	Put the Related Hydraulic System in the Depressurized Configuration before Maintenance Action
TASK 49-00-00-710-010-A	Operational Test of the APU
TASK 52-41-00-010-001-A	Open the APU Doors for Access
TASK 52-41-00-410-001-A	Close the APU Doors after Access
Igniter Lead

3. Job Set-up
Subtask 49-41-43-860-056-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.
(3) Make sure that a WARNING NOTICE(S) is 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).
(5) Make sure that the ACCESS PLATFORM 4M (13 FT)-ADJUSTABLE is in position below the APU compartment.
(6) Make sure that the APU access doors 315AL and 316AR are open (Ref. AMM TASK 52-41-00-010-001).
(7) Make sure that the LIGHT switch control 11LJ is set in the ON position.
(8) Make sure that low-tension connector P10 is disconnected from the ignition exciter.

Subtask 49-41-43-865-059-A ** ON A/C NOT FOR ALL

B. Make sure that this(these) circuit breaker(s) is(are) open, safetied and tagged:

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

4. Procedure
Subtask 49-41-43-420-052-A ** ON A/C NOT FOR ALL

A. Installation of the Igniter Electrical Lead
(1) Do an inspection of the component interfaces and the adjacent area.
(2) Clean the component interfaces and the adjacent area.
(3) Remove the CAP-BLANKING from each electrical connector and receptacle.
(4) Connect the spring end of the igniter electrical lead (2) to the ignition unit (4).
(5) Connect the non-spring end of the igniter electrical lead (2) to the igniter plug (3).
(6) TORQUE the two connector nuts of the igniter electrical lead (2) to between 2.66 and 2.42 m.daN (19.62 and 17.85 lbf.ft )

.
(7) Connect the electrical connector (1).

Subtask 49-41-43-865-060-A ** ON A/C NOT FOR ALL

B. Make sure that this(these) circuit breaker(s) is(are) closed:

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

Subtask 49-41-43-710-052-A ** ON A/C NOT FOR ALL

C. Operational Test
(1) Do the operational test of the APU (Ref. AMM TASK 49-00-00-710-010).

5. Close-up
Subtask 49-41-43-410-052-A ** ON A/C NOT FOR ALL

A. Close Access
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Close APU access doors 315AL 316AR (Ref. AMM TASK 52-41-00-410-001).
(3) Remove the access platform(s).

Subtask 49-41-43-860-057-A ** ON A/C NOT FOR ALL

B. Aircraft Maintenance Configuration
(1) Put the related hydraulic system in the pressurized configuration (Ref. AMM TASK 29-00-00-864-001).
(2) De-energize the ground service network
(Ref. AMM TASK 24-42-00-862-001).
(3) Remove the WARNING NOTICE(S).

[Rev.10 from 2021] 2026.04.01 01:30:21 UTC