Operational Check of the Manual Switch Over

TASK 52-51-00-710-009-A
Operational Check of the Manual Switch Over

ZONE: 220

1. Reason for the Job
Refer to the MPD TASK: 525111-03
OPERATIONAL CHECK OF MANUAL SWITCH OVER
2. Job Set-up Information
A. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
220	FWD CAB UTILITY AREAS

B. 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

3. Job Set-up
Subtask 52-51-00-860-106-A

A. Aircraft Maintenance Configuration
(1) Make sure that the cockpit door is closed.
(2) Energize the ground service network
(Ref. AMM TASK 24-42-00-861-001).

Subtask 52-51-00-865-091-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 52-51-00-710-060-A

A. Operational Test of the Manual Switch Over
(1) Do the operational test to make sure that:

the control unit 28MQ is serviceable
the OPEN and FAULT lights of the pushbutton switch 27MQ operate correctly
the back-up system operates satisfactorily.

ACTION	RESULT
1.On the CKPT DOOR BKUP panel of the Overhead Panel 45VU:	On the CKPT DOOR BKUP panel and on the COCKPIT DOOR panel:
set the NORM/BKUP/OFF switch 21MQ in the BKUP position.	no FAULT lamp is illuminated.
	On the Cockpit Door:
	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.
2.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.
3.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.
4.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.
5.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.
6.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.	the electrical release strikes 30MQ, 31MQ and 32MQ stay energized the cockpit door stays in the locked condition and you cannot open it from the cabin side.

5. Close-up
Subtask 52-51-00-860-107-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 ground service network
(Ref. AMM TASK 24-42-00-862-001).

[Rev.10 from 2021] 2026.04.02 06:28:23 UTC