Loss of the Interface between Radio Altimeter Antennas and Transceiver 2

TASK 34-42-00-810-840-A
Loss of the Interface between Radio Altimeter Antennas and Transceiver 2

1. Possible Causes

2. Job Set-up Information
A. Consumable Materials

REFERENCE	DESIGNATION
(Material No.08BBD1)	Non Aqueous Cleaner-- Isopropyl Alcohol -
(Material No.14SBA1)	Textile-Lint free Cotton -

B. Referenced Information

REFERENCE	DESIGNATION
ESPM 2044220
AMM 34-42-00-740-002	BITE Test of the Radio Altimeter
AMM 34-42-11-000-001	Removal of the Radio Altimeter Antenna
AMM 34-42-11-400-001	Installation of the Radio Altimeter Antenna
AMM 34-42-11-615-001	Cleaning of the External Surface of the Radio Altimeter Antennas
AMM 34-42-11-920-001	Radio Altimeter Antennas and Coaxial Cables Replacement
AMM 34-42-33-000-001	Removal of the Radio Altimeter Transceiver
AMM 34-42-33-400-001	Installation of the Radio Altimeter Transceiver

3. Fault Confirmation
Subtask 34-42-00-740-112-A

A. Test
Do the BITE test of the radio altimeter AMM 34-42-00-740-002.

4. Fault Isolation
Subtask 34-42-00-810-093-A

A. If the test gives no maintenance message:

NOTE: If there is a maintenance message, refer to the related trouble shooting procedure.

Make sure that there are no objects (such as towbar) in the area near the Radio Altimeter (RA) antennas.
Make sure there is no water below the RA antennas, on ground and between the antennas and the ground.
Clean the external surface of the RA antennas with Non Aqueous Cleaner-- Isopropyl Alcohol - (Material No.08BBD1) and a Textile-Lint free Cotton - (Material No.14SBA1) AMM 34-42-11-615-001.

(1) If the fault continues:

swap the XCVR-RA, 2 [2SA2] and the radio altimeter transceiver 1 AMM 34-42-33-000-001 and AMM 34-42-33-400-001.

(a) If the fault stops:

(b) If the fault continues:

1 If the ARINC 600 connectors are not in correct condition:

2 If the ARINC 600 connectors are in correct condition:

remove the ANTENNA-RA RCPTN, 2 [5SA2] and the ANTENNA-RA XMSN, 2 [6SA2] AMM 34-42-11-000-001
check if the antenna coaxial cables are in correct condition (no corrosion).

a If the antenna coaxial cables are not in correct condition:

b If the antenna coaxial cables are in correct condition:

replace the ANTENNA-RA RCPTN, 2 [5SA2] and the ANTENNA-RA XMSN, 2 [6SA2] AMM 34-42-11-400-001 and AMM 34-42-11-000-001.

Subtask 34-42-00-810-112-A

B. If the fault continues:

Subtask 34-42-00-740-113-A

C. Do the test given in Para. 3.

[Rev.8 from Aug 2018] 2026.04.04 04:33:10 UTC