Operational Test of the Back-Up System

TASK 52-51-00-710-004-A
Operational Test of the Back-Up System

1. Reason for the Job
Self explanatory
2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
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)

3. Job Set-up
Subtask 52-51-00-860-073-A

A. Aircraft Maintenance Configuration
(1) Make sure that the cockpit door is closed.
(2) Energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-861-002).

Subtask 52-51-00-865-064-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
122VU	DOORS/PAX/MONG	1MQ	T13
122VU	CKPT/OVRD SYS/SPLY	4MQ	S10

4. Procedure
Subtask 52-51-00-710-055-A

A. Operational Test of the Back-Up System
(1) Do the operational test to make sure that:

the control units 24MQ and 28MQ are servicable,
the OPEN and FAULT lights of the indication light 22MQ operate correctly,
the OPEN and FAULT lights of the pushbutton switch 27MQ operate correctly,
the back-up system operates satisfactorily.

ACTION	RESULT
1.On the Circuit Breaker Panel 122VU:	On the Cockpit Door:
open the circuit breakers 1MQ and 4MQ.	the electrical release strikes 30MQ, 31MQ and 32MQ are de-energized the cockpit door is in the unlocked condition and you can open it from the cabin side.
close the circuit breakers 1MQ and 4MQ.	the electrical release strikes 30MQ, 31MQ and 32MQ are energized the cockpit door is in the locked condition and you cannot open it from the cabin side.
2.On the CKPT DOOR BKUP panel of the Overhead Panel 45VU:
open the guard and set the NORM/BKUP/OFF switch 21MQ in the OFF position.	the electrical release strikes 30MQ, 31MQ and 32MQ are de-energized the cockpit door is in the unlocked condition and you can open it from the cabin side.
	On the COCKPIT DOOR panel 119VU of the center pedestal: the FAULT lamp of the indication light 22MQ comes on.
	On the CKPT DOOR BKUP panel of the Overhead Panel 45VU: the FAULT lamp of the pushbutton switch 27MQ comes on.
3.On the CKPT DOOR BKUP panel of the Overhead Panel 45VU:	On the CKPT DOOR BKUP panel of the Overhead Panel 45VU:
set the NORM/BKUP/OFF switch 21MQ in the NORM position and guard it.	the FAULT lamp of the pushbutton switch 27MQ goes off.
	On the COCKPIT DOOR panel 119VU of the center pedestal: the FAULT lamp of the indication light 22MQ goes off.
	On the Cockpit Door: the electrical release strikes 30MQ, 31MQ and 32MQ are energized the cockpit door is in the locked condition and you cannot open it from the cabin side.
4.On the Overhead Panel 25VU:	On the COCKPIT DOOR panel 119VU of the center pedestal:
set the ANN LT switch 33LP to the TEST position.	the OPEN and the FAULT lamps of the indication light 22MQ come on.
	On the CKPT DOOR BKUP panel of the Overhead Panel 45VU: the OPEN and the FAULT lamps of the pushbutton switch 27MQ come on.
	On the CKPT DOOR CONT panel 20VU (control unit 24MQ): the three LEDs TOP, MID and BOT STRIKE come on. the two LEDs CHAN 1 and CHAN 2 come on.
	On the CKPT DOOR CONT panel (control unit 28MQ): the three LEDs TOP, MID and BOT STRIKE come on. the two LEDs CHAN 1 and CHAN 2 come on.
5.On the Overhead Panel 25VU:	On the CKPT DOOR CONT panel 20VU (control unit 24MQ):
set the ANN LT switch 33LP in BRT position.	the LEDs TOP, MID and BOT STRIKE go off, the LEDs CHAN 1 and CHAN 2 go off.
	On the CKPT DOOR CONT panel (control unit 28MQ): the three LEDs TOP, MID and BOT STRIKE go off, the two LEDs CHAN 1 and CHAN 2 go off.
	On the COCKPIT DOOR panel 119VU: the OPEN and the FAULT lamps of the indicator light 22MQ go off.
	On the CKPT DOOR BKUP panel of the Overhead Panel 45VU: the OPEN and the FAULT lamps of the pushbutton switch 27MQ go off.
6.On the CKPT DOOR BKUP panel of the Overhead Panel 45VU:	On the Cockpit Door:
set the NORM/BKUP/OFF switch 21MQ in the BKUP position.	the electrical release strikes 30MQ, 31MQ and 32MQ stay energized the cockpit door is in the locked condition and you cannot open it from the cabin side.
7.On the Cockpit Door:	On the Cockpit Door:
turn the D-ring of the door latch mechanism and move the door in the open direction.	the tenons of the door latch mechanism retract and the cockpit door is unlocked. the cockpit door moves in the open direction.
	On the CKPT DOOR BKUP panel of the Overhead Panel 45VU: the OPEN lamp of the pushbutton switch 27MQ comes on.
close the door.	the OPEN lamp of the pushbutton switch 27MQ goes off.
	On the Cockpit Door: the door latch mechanism locks the closed cockpit door automatically.
8.On the CKPT DOOR BKUP panel of the Overhead Panel 45VU:
push and hold the pushbutton switch 27MQ.	the electrical release strikes 30MQ, 31MQ and 32MQ are de-energized the cockpit door is in the unlocked condition and you can open it from the cabin side.
9.On the Cockpit Door:	On the CKPT DOOR BKUP panel of the Overhead Panel 45VU:
move the cockpit door in the open direction.	the OPEN lamp of the pushbutton switch 27MQ comes on.
10.On the CKPT DOOR BKUP panel of the Overhead Panel 45VU:	On the Cockpit Door:
release the pushbutton switch 27MQ.	the electrical release strikes 30MQ, 31MQ and 32MQ are energized.
11.On the Cockpit Door:	On the Cockpit Door:
move the cockpit door in the close direction.	the door latch mechanism locks the closed cockpit door automatically.
	On the CKPT DOOR BKUP panel of the Overhead Panel 45VU: the OPEN lamp of the pushbutton switch 27MQ goes off.
12.On the CKPT DOOR BKUP panel of the Overhead Panel 45VU:	On the Cockpit Door:
set the NORM/BKUP/OFF switch 21MQ to the NORM position and make sure that the guard is closed.	the electrical release strikes 30MQ, 31MQ and 32MQ stay energized the cockpit door remains in the locked condition and you cannot open it from the cabin side.

5. Close-up
Subtask 52-51-00-860-074-A

A. Put the aircraft back to the serviceable condition.
(1) Make sure that the work area is clean and clear of tools and other items.
(2) De-energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-862-002).

[Rev.10 from 2021] 2026.04.02 07:23:54 UTC