Operational Test of the Automatic Switching of the MCDUs

TASK 22-70-00-710-003-A
Operational Test of the Automatic Switching of the MCDUs

WARNING: MAKE SURE THAT ALL THE CIRCUITS IN MAINTENANCE ARE ISOLATED BEFORE YOU SUPPLY ELECTRICAL POWER TO THE AIRCRAFT. UNWANTED ELECTRICAL POWER CAN BE DANGEROUS.

ZONE: 210

1. Reason for the Job
To make sure that the automatic switching of the MCDUs occurs correctly when one FMGC does not operate.
2. Job Set-up Information
A. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
210	CKPT,FWD COMPT BHD TO FLT COMPT BULKHEAD

B. 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 22-70-00-860-057-A

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

Subtask 22-70-00-865-055-A

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

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
49VU	AUTO FLT/FMGC/1	10CA1	B02
49VU	AUTO FLT/MCDU/1	11CA1	B01
** ON A/C NOT FOR ALL
49VU	AUTO FLT/FMGC/1	10CA1	H08
49VU	AUTO FLT/MCDU/1	11CA1	H07
** ON A/C ALL
121VU	AUTO FLT/FMGC/2	10CA2	M17
121VU	AUTO FLT/MCDU/2	11CA2	N20

4. Procedure
Subtask 22-70-00-710-055-B

A. Operational Test of the Automatic Switching of the MCDUs

NOTE: This test is for the system 1. For the system 2, use the indications between the parentheses.

ACTION	RESULT
1.On the center pedestal, on the MCDU1 and the MCDU2, Adjust the display brightness with the BRT and DIM keys.
On the MCDU1 and the MCDU2, push the MCDU MENU mode key.	The MCDU MENU page comes into view.
On the MCDU1 and the MCDU2, push the line key adjacent to the FMGC indication.	On the two MCDUs, a FM page comes into view.
On the MCDU1(2), push the INIT mode key.	On the MCDU1(2), the INIT page comes into view.
On the MCDU2(1), push the DATA mode key.	On the MCDU2(1), the DATA INDEX page comes into view.
On the MCDU2(1), push the line key adjacent to the A/C STATUS indication.	On the MCDU2(1), the A/C STATUS page comes into view.
2.Open the circuit breaker 10CA1(2).	On the MCDU1(2), the SUBSYSTEM page comes into view (with the FMGC TIME OUT and PRESS MCDU MENU KEY indications in view).
3.On the center pedestal, on the MCDU1(2)
Push the MCDU MENU mode key.	The MCDU MENU page comes into view.
Push the line key adjacent to the FMGC indication.	On the MCDU1(2), the INIT page comes into view (with the OPP FMGC IN PROCESS indication in view).
Push the CLR function key.	On the MCDU1(2), the OPP FMGC IN PROCESS indication goes out of view.
4.Close the circuit breaker 10CA1(2).	On the MCDU1(2), the SUBSYSTEM page comes into view after some minutes (with the FMGC TIME OUT and PRESS MCDU MENU KEY indications in view).
5.On the center pedestal, on the MCDU1(2), push the MCDU MENU mode key.	On the two MCDUs, the A/C STATUS pages come into view. The PLEASE WAIT indications come into view. After the resynchronization time, the PLEASE WAIT indications go out of view.

5. Close-up
Subtask 22-70-00-862-053-A

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

[Rev.10 from 2021] 2026.03.31 23:10:56 UTC