Loss of the Datalink Communication

TASK 46-21-00-810-844-A
Loss of the Datalink Communication

1. Possible Causes

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
TSM TASK 46-21-00-810-815-A	Loss of the VDR3 Data Detected by the ATSU
AMM 23-12-00-740-001	BITE Test of the VHF System
AMM 46-21-00-740-001	BITE Test of the ATIMS
AMM 46-21-00-860-001	Initialization Procedure of the ATSU Router

3. Fault Confirmation
Subtask 46-21-00-740-134-A

A. Test
Make sure that the ACARS STBY or COMPANY DATALINK STBY right memo is shown on the upper ECAM DU.

4. Fault Isolation
Subtask 46-21-00-810-094-A ** ON A/C NOT FOR ALL

A. On the MCDU, get access to the COMM INIT page as shown in the initialization procedure of the ATSU router AMM 46-21-00-860-001.
On the COMM INIT page, make sure that the mandatory parameters are correct:

The airline identification codes (codes with two and three digits)
The A/C registration number
The VHF3 SCAN MASK.

(1) If the parameters are not correct:

Enter the correct parameters as shown in the initialization procedure of the ATSU router.

(2) If the parameters are correct:

Get access to the COMM STATUS page
On this page, make sure that the VDR3 is operational .

(a) If the VHF3 is not operational:

Do the trouble shooting procedure (Ref. TSM TASK 46-21-00-810-815).

(b) If the VHF3 is operational:

Get access to the VHF3 DATA MODE page
Make sure that the frequency and the name of the Datalink Service Provider (DSP) shown on this page are those of a DSP available in the area.

1 If the DSP and the frequency are available in the area:

On the MCDU, push the line key adjacent to the related DSP (this causes the ATSU to tune on the frequency of this service provider).
The ATSU will do automatic link tests with the ground to make the aircraft-ground link.

a If the ATSU makes the link:

The ACARS STBY or DATALINK STBY right memo goes out of view and no other maintenance action is necessary.

b If the ATSU does not make the link and no other ECAM memo/warning is shown:

Do the BITE tests of the ATSU AMM 46-21-00-740-001 and of the VDR3 AMM 23-12-00-740-001.
. If the BITE tests are OK:
..The cause of the fault is external to the aircraft (saturated network, VHF reception unsatisfactory, etc.) and no other maintenance action is necessary.
. If the BITE are not OK:
.. Do the trouble shooting procedure related to the maintenance message(s).

2 If the ATSU uses a DSP/frequency for which the airline is not a subscriber:

Enter a new SCAN MASK
Set a new DSP for which the airline is a subscriber as shown in the initialization procedure of the ATSU router.

a If the new DSP is not available in this area:

The ACARS STBY or DATALINK STBY right memo will be shown again on the upper ECAM DU.

Subtask 46-21-00-810-094-C ** ON A/C NOT FOR ALL

A. On the MCDU, get access to the COMM CONFIG page as shown in the initialization procedure of the ATSU router AMM 46-21-00-860-001.
On the COMM CONFIG page, make sure that the mandatory parameters are correct:

The airline identification codes (codes with two and three digits)
The aircraft registration number
The VHF scan mask through the MCDU VHF3 SCAN SELECT menu.

(1) If the parameters are not correct:

Enter the correct parameters as shown in the initialization procedure of the ATSU router.

(2) If the parameters are correct:

Go to Para. 4.B to continue the troubleshooting.

Subtask 46-21-00-810-117-C ** ON A/C NOT FOR ALL

B. On the MCDU, get access to the DATALINK STATUS page.
On the DATALINK STATUS page, make sure that VHF3 is serviceable.
(1) If VHF3 is not serviceable:

Do the troubleshooting procedure (Ref. TSM TASK 46-21-00-810-815).

(2) If VHF3 is serviceable:

On the MCDU, get access to the VHF3 DATA MODE page.
Make sure that the frequency and the name of the datalink service provider (shown on the second line of the page) are available in the area.

(a) If they are available in the area and if the ATSU does not connect to the data service provider (with no other ECAM memo/warning):

SCAN is shown on the second line of the VHF3 DATA MODE page.
Do the BITE tests of the ATSU AMM 46-21-00-740-001 and VDR3 AMM 23-12-00-740-001.

1 If the BITE tests are OK:

The cause of the fault is not related to the aircraft (saturated network, VHF reception unsatisfactory, etc.) and no other maintenance procedure is necessary.
If the VHF reception is satisfactory and no communication is possible, send a report to the VHF data service-provider (subscribed by the airline).

2 If the BITE tests are not OK:

Do the troubleshooting procedure related to the maintenance message(s).

(b) If they are not available in the area:

Go to Para. 4.C. to continue the troubleshooting.

Subtask 46-21-00-810-118-C ** ON A/C NOT FOR ALL

C. Do the steps that follow:
(1) If a different data service provider is available in the area and is subscribed by the airline:

On the VHF3 DATA MODE page, push the line key adjacent to the service provider (the ATSU will tune to the frequency of this service provider).

(a) If the ATSU connects to the data service provider selected:

MANUAL is shown on the second line of the VHF3 DATA MODE page.
The COMPANY DATALINK STBY memo goes out of view.

(b) If the ATSU does not connect to the data service provider selected and no other ECAM memo/warning is shown:

Do the BITE tests of the ATSU AMM 46-21-00-740-001 and VDR3 AMM 23-12-00-740-001.

1 If the BITE tests are OK:

The cause of the fault is not related to the aircraft (saturated network, VHF reception unsatisfactory, etc.) and no other maintenance procedure is necessary.
If the VHF reception is satisfactory and no communication is possible, send a report to the VHF data service-provider (subscribed by the airline).

2 If the BITE tests are not OK:

Do the trouble shooting procedure related to the maintenance message(s).

(2) If no data service provider is available in the area:

Enter a new VHF scan mask.
Set a new data service provider which is available in the area (as shown in the initialization procedure of the ATSU router).
Do the procedure from Para 4.B. again.

Subtask 46-21-00-810-119-C ** ON A/C NOT FOR ALL

D. On the MCDU, on the DATALINK STATUS page, make sure that the SATCOM is serviceable (if the SDU is installed).
(1) If the SATCOM is not serviceable:

Do the troubleshooting procedure (Ref. TSM TASK 46-21-00-810-816).

(2) If the SATCOM is serviceable but the SATCOM status shown is 'DLK NOT AVAIL':

Do the BITE test of the ATSU AMM 46-21-00-740-001.

NOTE: If the SDU has a BITE function, it is necessary to do the BITE test of the SDU.

(a) If the BITE test is OK:

Do a check of the SDU configuration.

1 If the SDU configuration is incorrect:

Correct the SDU configuration.

2 If the SDU configuration is correct:

The cause of the fault is not related to the aircraft and no other maintenance procedure is necessary.
If the SDU configuration is correct and no communication is possible, send a report to the SATCOM data service-provider (subscribed by the airline).

(b) If the BITE tests are not OK:

Do the troubleshooting procedure related to the maintenance message(s).

Subtask 46-21-00-740-169-A

E. Do the test given in Para. 3.

[Rev.8 from Aug 2018] 2026.04.04 04:34:21 UTC