Test of the Engine SQUIB Legend of the AGENT Pushbutton Switch

TASK 26-21-00-040-003-A
Test of the Engine SQUIB Legend of the AGENT Pushbutton Switch

WARNING: MAKE SURE THAT THE ENG1(2) FIRE PUSHBUTTON SWITCH IS PUSHED IN BEFORE YOU START THE TEST.

CAUTION: TO RESET THE ENG 1(2) APU FIRE PUSHBUTTON SWITCH:

PUSH THE PUSHBUTTON SWITCH FULLY IN (LATCHED POSITION).

THEN CLOSE THE GUARD. DO NOT TRY TO CLOSE THE GUARD AND PUSH THE PUSHBUTTON SWITCH AT THE SAME TIME.

ZONE: 210
ZONE: 415
ZONE: 425
FIN: 6WE1
FIN: 6WE2
FIN: 8WE1
FIN: 8WE2
Task Summary

Access	Test	Specific Tools	Mhr	E/T	Nb Men
YES	YES	YES	0.5	1.5	3

1. Reason for the Job
MMEL 26-01-01-03A
ENG AGENT SQUIB
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	1	ACCESS PLATFORM 2M (6 FT) - ADJUSTABLE
No specific	AR	SAFETY CLIP - CIRCUIT BREAKER
No specific	1	VOLTMETER - DC
No specific	AR	WARNING NOTICE(S)
53100141-1	1	PLUG, SHUNT
OR	OR
M83723-60-18AN	1	CAP, PROTECTIVE

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
210	CKPT,FWD COMPT BHD TO FLT COMPT BULKHEAD
415	LOWER PYLON
425	LOWER PYLON
FOR [6WE1] (BOTTLE 1-FIRE EXTING, ENG 1)
415BL
FOR [6WE1] (BOTTLE 1-FIRE EXTING, ENG 1)
FOR [8WE1] (BOTTLE 2-FIRE EXTING, ENG 1)
415BL
FOR [6WE2] (BOTTLE 1-FIRE EXTING, ENG 2)
425BL
FOR [8WE1] (BOTTLE 2-FIRE EXTING, ENG 1)
415BR
415CR
FOR [8WE2] (BOTTLE 2-FIRE EXTING, ENG 2)
425CR
425BR

C. Referenced Information

REFERENCE	DESIGNATION
TASK 20-15-00-910-001-A	Handling Precautions for Electrostatic Discharge Sensitive Devices
TASK 24-41-00-861-002-A	Energize the Aircraft Electrical Circuits from the External Power
TASK 24-41-00-861-002-A-01	Energize the Aircraft Electrical Circuits from the APU
TASK 24-41-00-861-002-A-02	Energize the Aircraft Electrical Circuits from Engine 1(2)
TASK 24-41-00-862-002-A	De-energize the Aircraft Electrical Circuits Supplied from the External Power
TASK 24-41-00-862-002-A-01	De-energize the Aircraft Electrical Circuits Supplied from the APU
TASK 24-41-00-862-002-A-02	De-energize the Aircraft Electrical Circuits Supplied from the Engine 1(2)
TASK 26-12-00-710-001-A	Operational Check of Loop/Squib
TASK 26-21-41-000-004-A	Removal of the Cartridge of the Engine Fire-Extinguisher Bottle
TASK 26-21-41-000-004-C	Removal of the Cartridge of the Engine Fire-Extinguisher Bottle
TASK 26-21-41-400-004-A	Installation of the Cartridge of the Engine Fire-Extinguisher Bottle
TASK 26-21-41-400-004-C	Installation of the Cartridge of the Engine Fire-Extinguisher Bottle
TASK 29-10-00-710-001-A	Operational Check of Hydraulic Fire Shut Off Valves and Associated Indicating System
TASK 54-51-21-000-001-A	Removal of the Pylon Lateral Access-Doors
TASK 54-51-21-000-802-A	Removal of the Pylon Lateral Access-Doors
TASK 54-51-21-400-001-A	Installation of the Pylon Lateral Access-Doors
TASK 54-51-21-400-802-A	Installation of the Pylon Lateral Access-Doors

3. Job Set-up
Subtask 26-21-00-861-055-A

A. Energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-861-002).

Subtask 26-21-00-941-057-A

B. Safety Precautions
(1) Make sure that the engine shutdown occurred five minutes or more before you do this procedure.
(2) In the cockpit, on the center pedestal, on ENG panel 115VU:
(a) Make sure that the ENG/MODE/CRANK/NORM/IGN/START selector switch is in the NORM position.
(b) Put the WARNING NOTICE(S) in position to tell persons not to start the engine.
(3) In the cockpit, on maintenance panel 50VU:
(a) Make sure that the ON legend of the ENG/FADEC GND PWR/1(2) pushbutton switch is off.
(b) Put the WARNING NOTICE(S) in position to tell persons not to energize FADEC 1(2).

Subtask 26-21-00-865-060-A

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

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
121VU	ENGINE/ENG1 AND 2 FIRE EXTIG/BTL1/SQUIB/B	2WE1	Q44
121VU	ENGINE/ENG1 AND 2 FIRE EXTIG/BTL2/SQUIB/B	2WE2	Q42
** ON A/C NOT FOR ALL
121VU	ENGINE/ENG1 AND 2 FIRE EXTIG/BTL1/SQUIB/A	1WE1	Q43
121VU	ENGINE/ENG1 AND 2 FIRE EXTIG/BTL2/SQUIB/A	1WE2	Q41
** ON A/C NOT FOR ALL
121VU	ENGINE/ENG1 AND 2 FIRE EXTIG/BTL2/SQUIB/B	2WE1	Q44
121VU	ENGINE/ENG1 AND 2 FIRE EXTIG/BTL1/SQUIB/B	2WE2	Q42
** ON A/C NOT FOR ALL
121VU	ENGINE/ENG1 AND 2 FIRE EXTIG/BTL2/SQUIB/B	2WE1	Q43
121VU	ENGINE/ENG1 AND 2 FIRE EXTIG/BTL1/SQUIB/A	1WE1	Q42
121VU	ENGINE/ENG1 AND 2 FIRE EXTIG/BTL1/SQUIB/B	2WE2	Q41
121VU	ENGINE/ENG1 AND 2 FIRE EXTIG/BTL2/SQUIB/A	1WE2	Q40

Subtask 26-21-00-010-057-A ** ON A/C NOT FOR ALL

D. Get Access
(1) Put the ACCESS PLATFORM 2M (6 FT) - ADJUSTABLE in position below the engine pylon.
(2) Remove the access doors (Ref. AMM TASK 54-51-21-000-001):
(a) FOR [6WE1] (BOTTLE 1-FIRE EXTING, ENG 1), [8WE1] (BOTTLE 2-FIRE EXTING, ENG 1)
415BL.
(b) FOR [8WE1] (BOTTLE 2-FIRE EXTING, ENG 1)
415BR.
(c) FOR [6WE2] (BOTTLE 1-FIRE EXTING, ENG 2)
425BL.
(d) FOR [8WE2] (BOTTLE 2-FIRE EXTING, ENG 2)
425BR.

Subtask 26-21-00-010-057-B ** ON A/C NOT FOR ALL

D. Get Access
(1) Put the ACCESS PLATFORM 2M (6 FT) - ADJUSTABLE in position below the engine pylon.
(2) Remove the access doors (Ref. AMM TASK 54-51-21-000-802):
(a) FOR [6WE1] (BOTTLE 1-FIRE EXTING, ENG 1)
415BL.
(b) FOR [8WE1] (BOTTLE 2-FIRE EXTING, ENG 1)
415CR.
(c) FOR [6WE2] (BOTTLE 1-FIRE EXTING, ENG 2)
425BL.
(d) FOR [8WE2] (BOTTLE 2-FIRE EXTING, ENG 2)
425CR.

Subtask 26-21-00-020-051-B

E. Aircraft Maintenance Configuration

WARNING: DO NOT TOUCH THE CARTRIDGE BEFORE YOU DO THE PROCEDURE APPLICABLE TO DEVICES THAT ARE SENSITIVE TO ELECTROSTATIC DISCHARGE. ELECTROSTATIC DISCHARGE CAN CAUSE THE FIRE EXTINGUISHER BOTTLE TO RELEASE ITS CONTENTS SUDDENLY AND CAUSE INJURY TO PERSONS.

(1) Before you touch the cartridge, do the procedure for devices that are sensitive to electrostatic discharge (Ref. AMM TASK 20-15-00-910-001).
(2) In the engine pylon, on the engine fire extinguisher bottle, disconnect the electrical connectors from the cartridges:

For the engine 1: 5WE1-A (bottle 1) and 7WE1-A (bottle 2)
For the engine 2: 5WE2-A (bottle 1) and 7WE2-A (bottle 2).

(3) Put a 53100141-1 PLUG, SHUNTM83723-60-18AN CAP, PROTECTIVE on the cartridges.

Subtask 26-21-00-420-051-A

F. On the disconnected connectors, on the wiring side:

Connect the pin 1 to an aircraft grounding point.
Connect the pin 2 to an aircraft grounding point.

Subtask 26-21-00-865-061-A

G. Remove the safety clip(s) and the tag(s) and close this(these) circuit breaker(s):

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
121VU	ENGINE/ENG1 AND 2 FIRE EXTIG/BTL1/SQUIB/B	2WE1	Q44
121VU	ENGINE/ENG1 AND 2 FIRE EXTIG/BTL2/SQUIB/B	2WE2	Q42
** ON A/C NOT FOR ALL
121VU	ENGINE/ENG1 AND 2 FIRE EXTIG/BTL1/SQUIB/A	1WE1	Q43
121VU	ENGINE/ENG1 AND 2 FIRE EXTIG/BTL2/SQUIB/A	1WE2	Q41
** ON A/C NOT FOR ALL
121VU	ENGINE/ENG1 AND 2 FIRE EXTIG/BTL2/SQUIB/B	2WE1	Q44
121VU	ENGINE/ENG1 AND 2 FIRE EXTIG/BTL1/SQUIB/B	2WE2	Q42
** ON A/C NOT FOR ALL
121VU	ENGINE/ENG1 AND 2 FIRE EXTIG/BTL2/SQUIB/B	2WE1	Q43
121VU	ENGINE/ENG1 AND 2 FIRE EXTIG/BTL1/SQUIB/A	1WE1	Q42
121VU	ENGINE/ENG1 AND 2 FIRE EXTIG/BTL1/SQUIB/B	2WE2	Q41
121VU	ENGINE/ENG1 AND 2 FIRE EXTIG/BTL2/SQUIB/A	1WE2	Q40

4. Procedure
Subtask 26-21-00-710-055-A

CAUTION: MAKE SURE YOU WILL NOT CAUSE UNWANTED CHANGES TO OTHER SYSTEMS BEFORE YOU PUSH THE ENG1(2) FIRE PUSHBUTTON SWITCH. WHEN YOU PUSH THE ENG1(2) FIRE PUSHBUTTON SWITCH:

THESE VALVES CLOSE

. THE LP FUEL VALVE . THE HYDRAULIC FIRE VALVE . THE BLEED AIR VALVES . THE ANTI-ICE VALVES . THE AIR CONDITIONING PACK VALVES

THE GENERATOR STOPS.

A. Do this Test

ACTION	RESULT
1.On ENG/APU FIRE panel 1WD: Push and hold the TEST pushbutton switch.	On ENG/APU FIRE panel 1WD: The two SQUIB legends for ENG 1(2) come on.
Release the ENG 1(2) TEST pushbutton switch.	- The two SQUIB legends go off.

(1) If the result of the test in Para. 4.A. is correct, do the steps that follow. If the result of the test in Para. 4.A. is not correct, do step 4.D.

Subtask 26-21-00-960-050-A

B. Replace the cartridge
(Ref. AMM TASK 26-21-41-000-004) and (Ref. AMM TASK 26-21-41-400-004).

Subtask 26-21-00-710-067-A

C. Do steps that follow:
(1) Disconnect pins 1 and 2 from the aircraft grounding points.
(2) Remove the shunt devices from the cartridges.
(3) Connect connectors 5WE1-A (5WE2-A) and 7WE1-A (7WE2-A) to their cartridges.
(4) Make sure that the connectors are correctly connected.
(5) Do an operational test of the engine fire and overheat detection (loop/squib) (Ref. AMM TASK 26-12-00-710-001).

Subtask 26-21-00-710-068-A

D. If the result of the test in Para. 4.A. is not correct (one or two legends of the related engine are off), the firing test system is defective.
(1) Do the test that follows to make sure that the firing system operates correctly:

ACTION	RESULT
1. In the engine pylon: Connect the VOLTMETER - DC between: - Pin 1 and the grounding point - Pin 2 and the grounding point.	In the engine pylon: Make sure that the VOLTMETER - DC shows 0VDC.
2. On overhead panel, on ENG/APU FIRE panel 1WD: Lift the guard of the ENG 1(2) FIRE pushbutton switch.	On ENG/APU FIRE panel 1WD: Ignore the SQUIB legends.
3. On overhead panel, on ENG/APU FIRE panel 1WD: Push, then release the ENG 1(2) FIRE pushbutton switch. Push and hold the related AGENT 1(2) pushbutton switch.	In the engine pylon: Make sure that the VOLTMETER - DC shows 28VDC between: - Pin 1 and the grounding point - Pin 2 and the grounding point.
4. On overhead panel, on ENG/APU FIRE panel 1WD: Release the AGENT 1(2) pushbutton switch.	In the engine pylon: Make sure that the VOLTMETER - DC shows 0VDC between: - Pin 1 and the grounding point - Pin 2 and the grounding point.
On ENG/APU FIRE panel 1WD: Lift the guard of the ENG 1(2) FIRE pushbutton switch. Push, then release the ENG 1(2) FIRE pushbutton switch.
3. In the related engine pylon: Disconnect the voltmeter(s).

(2) If the result of the test in Para. 4.D. is correct, do the steps that follow. If the result of the test in Para. 4.D. is not correct, do step 4.F.

Subtask 26-21-00-420-057-A

E. Do the steps that follow:
(1) If the firing system operates correctly but the firing test system is defective, the aircraft can continue in service.
(2) Disconnect the voltmeter.
(3) Remove the shunt plugs from the cartridges.
(4) Connect connectors 5WE1-A (5WE2-A) and 7WE1-A (7WE2-A) to their cartridges.
(5) Make sure that the connectors are correctly connected.
(6) On ENG/APU FIRE panel 1WD, close the guard of ENG 1(2) FIRE pushbutton switch.
(7) Do an operational test of the engine fire and overheat detection (loop/squib) (Ref. AMM TASK 26-12-00-710-001).
(8) Do an operational test of the hydraulic fire shut-off-valves (Ref. AMM TASK 29-10-00-710-001).

Subtask 26-21-00-350-050-A

F. If the result of the test in Para. 4.D. is not correct, repair the firing system.
(1) Do the troubleshooting of the firing system TSM 26.

5. Close-up
Subtask 26-21-00-410-057-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) Install the access doors (Ref. AMM TASK 54-51-21-400-001):
(a) FOR [6WE1] (BOTTLE 1-FIRE EXTING, ENG 1)
415BL.
(b) FOR [8WE1] (BOTTLE 2-FIRE EXTING, ENG 1)
415BR.
(c) FOR [6WE2] (BOTTLE 1-FIRE EXTING, ENG 2)
425BL.
(d) FOR [8WE2] (BOTTLE 2-FIRE EXTING, ENG 2)
425BR.
(3) Remove the WARNING NOTICE(S).
(4) Remove the access platform(s).
(5) Make an entry in the logbook.
(6) Put an applicable placard in position in the cockpit (refer to your standard practices and local regulations).

Subtask 26-21-00-410-057-B ** 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) Install the access doors (Ref. AMM TASK 54-51-21-400-802):
(a) FOR [6WE1] (BOTTLE 1-FIRE EXTING, ENG 1)
415BL.
(b) FOR [8WE1] (BOTTLE 2-FIRE EXTING, ENG 1)
415CR.
(c) FOR [6WE2] (BOTTLE 1-FIRE EXTING, ENG 2)
425BL.
(d) FOR [8WE2] (BOTTLE 2-FIRE EXTING, ENG 2)
425CR.
(3) Remove the WARNING NOTICE(S).
(4) Remove the access platform(s).
(5) Make an entry in the logbook.
(6) Put an applicable placard in position in the cockpit (refer to your standard practices and local regulations).

Subtask 26-21-00-862-055-A

B. De-energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-862-002).

[Rev.10 from 2021] 2026.03.31 23:44:29 UTC