Operational Test of the Back-up Mode

TASK 31-32-00-710-002-A
Operational Test of the Back-up Mode

NOTE: IGNORE ALL THE ECAM WARNINGS AS LONG AS THE COMPUTER IS IN THE MENU MODE.

ZONE: 210

1. Reason for the Job
Self explanatory
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)
TASK 31-32-00-860-008-A	Procedure to Get Access to the SYSTEM REPORT/TEST/INST Page

3. Job Set-up
Subtask 31-32-00-861-053-A

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

Subtask 31-32-00-865-053-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/MCDU/1	11CA1	B01
** ON A/C NOT FOR ALL
49VU	AUTO FLT/MCDU/1	11CA1	H07
** ON A/C NOT FOR ALL
121VU	CFDS/CFDIU/SPLY	2TW	J18
121VU	CFDS/CFDIU/BACK/UP	8TW	J17
** ON A/C NOT FOR ALL
121VU	CFDS/CFDIU/SPLY	2TW	J41
121VU	CFDS/CFDIU/BACK/UP	8TW	J40

4. Procedure
Subtask 31-32-00-970-056-A ** ON A/C NOT FOR ALL

A. Check the P/N of the CFDIU.
(1) Do the procedure to get the SYSTEM REPORT/TEST INST page (Ref. AMM TASK 31-32-00-860-008).

ACTION	RESULT
On the MCDU: 1.Push the line key adjacent to the CFDIU indication.	The CFDIU MENU page comes into view.
2.Push the line key adjacent to the LRU IDENTIFICATION indication.	The CFDIU LRU IDENTIFICATION page comes into view.
3.Write the P/N reference.
4.Push the line key adjacent to the RETURN indication until the MCDU MENU page comes into view.	The MCDU MENU page comes into view.

(2) Make sure that the P/N shown on the CFDIU LRU IDENTIFICATION page is
the same as the computer P/N (given on the front face).

NOTE: If the P/N is not the same, you must remove the computer and return it to the shop.
(3) If the P/N reference of the CFDIU starts:
(a) With B401XXXX, do the procedure in Para B.
(b) With C128XXXX, go to Para 5.

Subtask 31-32-00-710-051-A

B. Do this test:

ACTION	RESULT
1.Adjust the brightness of the MCDU 1 screen.	the MCDU 1 is on.
2.On the MCDU 1: push the MCDU MENU mode key.	On the MCDU 1: the MCDU MENU page comes into view.
3.On the panel 121VU: open the circuit breaker 2TW.	On the MCDU 1: after 5s approximately, on the MCDU MENU page, the CFDS indication goes out of view. after 30s approximately, on the MCDU MENU page, the CFDS indication comes into view again.
4.On the MCDU 1: push the line key adjacent to the CFDS indication.	On the MCDU 1: the CFDS BACK-UP MODE page comes into view.
5.On the MCDU 1: push the line key adjacent to the SYSTEM REPORT/TEST indication.	On the MCDU 1: the SYSTEM REPORT/TEST page comes into view.
6.On the MCDU 1: set a system menu. To do this, push the line key adjacent to the system indication.	On the MCDU 1: the menu page of the set system comes into view.
7.On the MCDU 1: push the line key adjacent to the RETURN indication.	On the MCDU 1: the SYSTEM REPORT/TEST page comes into view.
8.On the panel 121VU: close the circuit breaker 2TW.
9.On the MCDU 1: push the line key adjacent to the RETURN indication until the CFDS MENU page comes into view.	On the MCDU 1: the MCDU MENU page comes into view.

5. Close-up
Subtask 31-32-00-860-100-A

A. Put the aircraft back to its initial configuration.
(1) De-energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-862-002).
(2) Put the system back to the serviceable condition.
(3) Put the aircraft back to the serviceable condition.

[Rev.10 from 2021] 2026.04.01 00:34:01 UTC