Loss of the RA1 Data to the TCAS

TASK 34-43-00-810-817-A
Loss of the RA1 Data to the TCAS

1. Possible Causes

CMPTR-TCAS [1SG]
wiring of the RADIO ALTITUDE 1 bus from the TCAS computer (1SG) to the first terminal block

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 34-43-00-740-001	BITE Test of the TCAS
ASM 344301
AMM 34-43-34-000-001	Removal of the TCAS Computer
AMM 34-43-34-400-001	Installation of the TCAS Computer

3. Fault Confirmation
Subtask 34-43-00-740-076-A

A. Test
(1) Do the BITE test of the TCAS AMM 34-43-00-740-001.

4. Fault Isolation
Subtask 34-43-00-810-067-A

A. If the test gives the maintenance message RA1 (1SA1)/TCAS (1SG):

(1) If the fault continues:

do a check and repair the wiring of the RADIO ALTITUDE 1 bus from the TCAS computer (1SG) to the first terminal block ASM 344301.

Subtask 34-43-00-740-077-A

B. Do the test given in Para. 3.

[Rev.8 from Aug 2018] 2026.04.04 04:33:13 UTC