Procedure to Set the Clock

TASK 31-21-00-750-002-A
Procedure to Set the Clock

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 set:

The internal time of the clock
The clock time from the MMR data (GPS UTC time).

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)
TSM 34-36-00-810-897	Wrong GNSS Date on Aircraft
Different Types of Clocks

3. Job Set-up
Subtask 31-21-00-861-050-A

A. Aircraft Maintenance Configuration
(1) Energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-861-002).
(2) Make sure that the aircraft is in an open area (for type 3 clock only).

Subtask 31-21-00-865-053-A

B. Make sure that this(these) circuit breaker(s) is(are) open, safetied and tagged:

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C ALL
49VU	NAV/MMR/1	42RT1	G12
** ON A/C NOT FOR ALL
121VU	COM NAV/MMR/2	42RT2	K09
** 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	COM NAV/MMR/2	42RT2	L07
** ON A/C NOT FOR ALL
121VU	CFDS/CFDIU/SPLY	2TW	J41
121VU	CFDS/CFDIU/BACK/UP	8TW	J40

Subtask 31-21-00-865-050-A

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

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C ALL
49VU	CLOCK/NORM/SPLY	6FS	F11
121VU	CLOCK/STBY/SPLY	4FS	N02

4. Procedure

NOTE: Refer to this illustration to know what is your applicable type of clock.

Subtask 31-21-00-750-050-A

A. Set of the Type 1 Clock

NOTE: When you set the time or the date, only the numbers related to the position of the UTC selector switch are shown.
The number of minutes, hours, days, months or years increases when you turn the SET pushbutton switch.
The number decreases when you push the SET pushbutton switch.

ACTION	RESULT
On the clock: Set the UTC selector switch to MO.	The two numbers of the month come into view. Different Types of Clocks
Adjust the month with the SET pushbutton switch.
Adjust the year: - When the month changes from 12 (December) to 01 (January) in the MO display, the year increases in the ET display. - When the month changes from 01 (January) to 12 (December) in the MO display, the year decreases in the ET display.
Set the UTC selector switch to DY.	The two numbers of the day come into view. Different Types of Clocks
Adjust the day with the SET pushbutton switch.
Set the UTC selector switch to HR.	The two numbers of the hours come into view. Different Types of Clocks
Adjust the hours with the SET pushbutton switch.
Set the UTC selector switch to MIN.	The two numbers of the minutes come into view. Different Types of Clocks
Adjust the minutes with the SET pushbutton switch.
Set the UTC selector switch to RUN.	Time (hours and minutes) is shown.
Remove the safety clip(s) and the tag(s) and close this(these) circuit breaker(s): 42RT1, 42RT2, 2TW and 8TW.	The clock type 1 is initialized. Make sure that the time displayed on the lower ECAM display unit is in accordance with the clock. Go to the Para. Close-Up.

Subtask 31-21-00-750-056-A

B. Set of the Type 2 Clock

NOTE: When you set the time or the date, only the related numbers change. The other digits remain unchanged.
The number increases every second.

ACTION	RESULT
1.Set the hours: On the clock, set the UTC switch (right lower corner) from the RUN position to the HSD position.	The two left digits of the upper window increase. Different Types of Clocks
2.When the number for the hours is correct, set the UTC switch to the MSM position.	The two right digits of the upper window increase. Different Types of Clocks
3.When the number for the minutes is correct, set the UTC switch to the HLDY position.	The numbers for the hours and for the minutes stay the same.
4.Check these numbers: if they are not correct go back to step 4.B.1. If they are correct proceed to the following step:
5.Set the UTC selector switch to RUN.	The last right digit (tenth of minutes) increases while the numbers for the hours and the minutes stay the same until the right digit is reset.
6.Set the date: Press the DATE pushbutton switch once and set the UTC switch to the HSD position.	The days and months on the upper window, then the year are displayed in turn.
When the value for the days is correct, set the UTC switch to MSM.	The number for the days stays the same while the number for the months increases.
When the value for the months is correct, set the UTC switch to HLDY.	The numbers for the days and the months stay the same while the number for the year increases.
When the value for the years is correct, set the UTC switch to RUN.	The date is displayed (day, month and year).
Press the DATE pushbutton switch once.	The time of the day is displayed with the last smaller digit of the window increasing every six seconds. The clock is set.
Remove the safety clip(s) and the tag(s) and close this(these) circuit breaker(s): 42RT1, 42RT2, 2TW and 8TW.	The clock type 2 is initialized. Make sure that the time displayed on the lower ECAM display unit is in accordance with the clock. Go to the Para. Close-Up.

Subtask 31-21-00-750-055-A

C. Set of the Type 3 Clock (Internal Time Base)

NOTE: When you set the time or the date, only the digits that flash can change, the other digits remain unchanged.

NOTE: When you set the clock, you must enter the date of the current day.

ACTION	RESULT
1.Set the minutes: On the clock face, set the GPS/INT/SET (right middle section of the clock face) to the SET position.	The two digits for the minutes start to flash. Different Types of Clocks
Increase (or decrease) the value by turning the SET knob clockwise (or counterclockwise).	The two digits for the minutes increase (or decrease).
2.Set the hours: Press the SET knob once.	The two left digits for the hours start to flash. Different Types of Clocks
3.Increase (or decrease) the value for the hours by turning the SET knob clockwise (or counterclockwise).	The two left digits for the hours increase (or decrease).
4.Set the year: Press the SET knob once.	The two smaller digits at the right of the time window start to flash.
5.Increase (or decrease) the value for the year by turning the SET knob clockwise (or counterclockwise).	The two smaller right digits for the year increase (or decrease).
6.Set the month: Press the SET knob once.	The two left digits for the month start to flash.
Increase (or decrease) the value for the month by turning the SET knob clockwise (or counterclockwise).	The two left digits for the month increase (or decrease).
7.Set the day: Press the SET knob once.	The two digits for the days start to flash.
Increase (or decrease) the value for the days by turning the SET knob clockwise (or counterclockwise).	The two digits for the days increase (or decrease).
8.When all the necessary values are correct, start the time display at any time by turning the GPS/INT/SET switch to the INT position.	The two right digits for the seconds are reset (they display 00) and increase.
If the value for the seconds are known, move the selector switch to the INT position only when they must change from 59 to 00.	The clock internal-time base is set.
Remove the safety clip(s) and the tag(s) and close this(these) circuit breaker(s): 42RT1, 42RT2, 2TW and 8TW.	The clock type 3 is initialized. Make sure that the time displayed on the lower ECAM display unit is in accordance with the clock. Go to the Para. Close-Up.

Subtask 31-21-00-750-054-A

D. Setting of the Type 3 Clock (GPS UTC Time)

ACTION	RESULT
1.Remove the safety clip(s) and the tag(s) and close this(these) circuit breaker(s): 42RT1 and 42RT2.
2.On right center instrument-panel 400VU, at the clock: Set the GPS/INT/SET selector switch to GPS.	On right center instrument-panel 400VU: The clock shows the UTC time. The type 3 clock is set.
3.On right center instrument-panel 400VU, at the clock: Push the SET/DATE pushbutton switch.	On right center instrument-panel 400VU: The clock shows the date. Make sure that the clock shows the correct date. If the date is incorrect, do the troubleshooting procedure TSM 34-36-00-810-897.
4.Remove the safety clip(s) and the tag(s) and close this(these) circuit breaker(s): 2TW and 8TW.	Make sure that the time shown on the lower ECAM Display Unit (DU) agrees with the clock. Go to the Para. Close-up.

Subtask 31-21-00-865-057-A

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Subtask 31-21-00-860-054-A

DELETED

5. Close-up
Subtask 31-21-00-865-058-A

A. Table of the circuit breakers used in this procedure:

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

Subtask 31-21-00-860-055-A

B. Reset of the Flight Management and Guidance Computers (FMGC) (1CA1 and 1CA2)
(1) Do the reset of the FMGCs:
(a) Open this(these) circuit breaker(s):

10CA1
10CA2.

(b) Wait for a minimum of 15 seconds.
(c) Close this(these) circuit breaker(s):

10CA1
10CA2.

Subtask 31-21-00-860-051-A

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

[Rev.10 from 2021] 2026.04.01 00:33:21 UTC