Loss of the TCAS Data Input to the ATC/Mode S Transponder 1

TASK 34-52-00-810-822-A
Loss of the TCAS Data Input to the ATC/Mode S Transponder 1

1. Possible Causes

CMPTR-TCAS [1SG]
XPDR-ATC/MODE S, 1 [1SH1]
wiring from the TCAS computer (1SG) to the ATC/Mode S transponder 1 (1SH1)
wiring between the TCAS computer and the ATC/Mode S transponder 1

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 31-32-00-860-001	Procedure to Get Access to the SYSTEM REPORT/TEST Menu Page
AMM 34-43-00-740-001	BITE Test of the TCAS
AMM 34-43-34-000-001	Removal of the TCAS Computer
AMM 34-43-34-400-001	Installation of the TCAS Computer
AMM 34-52-00-720-005	Functional Test of the ATC/Mode S Transponder
AMM 34-52-00-740-004	BITE Test of the ATC
ASM 345201
AMM 34-52-33-000-001	Removal of the ATC/Mode S Transponder
AMM 34-52-33-400-001	Installation of the ATC/Mode S Transponder

3. Fault Confirmation
Subtask 34-52-00-740-084-A ** ON A/C NOT FOR ALL

A. Test
(1) Do the BITE test of the ATC AMM 34-52-00-740-004.

Subtask 34-52-00-740-084-C ** ON A/C NOT FOR ALL

A. Not applicable, you cannot confirm this fault on the ground.

4. Fault Isolation
Subtask 34-52-00-810-077-A ** ON A/C NOT FOR ALL

A. If the test gives the maintenance message TCAS (1SG)/ATC1 (1SH1):

replace the CMPTR-TCAS [1SG] AMM 34-43-34-000-001 and AMM 34-43-34-400-001.

(1) If the fault continues:

do the functional test of the ATC1 AMM 34-52-00-720-005.

(a) If the test is incorrect:

replace the XPDR-ATC/MODE S, 1 [1SH1] AMM 34-52-33-000-001 and AMM 34-52-33-400-001.

(b) If the test is correct:

do a check and repair the wiring from the TCAS computer (1SG) to the ATC/Mode S transponder 1 (1SH1) ASM 345201.

Subtask 34-52-00-810-077-H ** ON A/C NOT FOR ALL

A. If the fault symptom is identified by the maintenance message ATC-1:NO DATA FROM TCAS:
(1) Do the BITE test of the TCAS AMM 34-43-00-740-001.
(2) Do the BITE test of the ATC AMM 34-52-00-740-004.
(3) Print the Trouble Shooting Data (TSD) of the TCAS as follows:

Get access to the SYSTEM REPORT/TEST menu page AMM 31-32-00-860-001.
On the SYSTEM REPORT/TEST page, push the line key adjacent to the TCAS indication.
On the TCAS page, push the line key adjacent to the TROUBLE SHOOTING DATA indication.
Print the TSD.

(a) Make sure that all the conditions that follow are OK:

The BITE test of the TCAS does not give maintenance message.
The BITE test of the ATC does not give maintenance message.
No TROUBLE SHOOTING DATA entries were recorded during the last flight leg on which the 'ATC-1:NO DATA FROM TCAS' fault was recorded.
The TCAS reset does not occur during two flights that occur one after the other or two times by flight.

1 If all the conditions are OK, no other maintenance action is necessary.
2 If no, replace the CMPTR-TCAS [1SG] AMM 34-43-34-000-001 and AMM 34-43-34-400-001.
(b) If the fault continues:

Do the functional test of the ATC1 AMM 34-52-00-720-005.

1 If the test is incorrect:

Replace the XPDR-ATC/MODE S, 1 [1SH1] , AMM 34-52-33-000-001 and AMM 34-52-33-400-001.

2 If the test is correct:

Remove the TCAS computer and the ATC/Mode S transponder 1.
Do a check and repair the wiring between the TCAS computer and the ATC/Mode S transponder 1 between pins AE/15J,15K and pins AA/5E,5F ASM 345201.
Install the TCAS computer and the ATC/Mode S transponder 1.

Subtask 34-52-00-740-085-A ** ON A/C NOT FOR ALL

B. Do the test given in Para. 3.

[Rev.8 from Aug 2018] 2026.04.04 04:33:24 UTC