Failure of Coaxial Cable J3 of the TCAS Bottom Antenna

TASK 34-43-00-810-815-A
Failure of Coaxial Cable J3 of the TCAS Bottom Antenna

1. Possible Causes

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 34-43-00-740-001	BITE Test of the TCAS
ASM 344301
AMM 34-43-11-000-001	Removal of the TCAS Antenna
AMM 34-43-11-400-001	Installation of the TCAS Antenna
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 34-43-00-740-072-A

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

4. Fault Isolation
Subtask 34-43-00-810-157-F ** ON A/C NOT FOR ALL

A. If the test gives the maintenance message TCAS BOT ANTENNA(7SG2)COAXIAL J3:

(1) Do a check of the resistance between:

The core and the shield of coaxial cable J3 (33200 ohms +/- 3320 ohms) ASM 344301.

(a) If the resistance value is in the specified limits:

(b) If the resistance value is out of the specified limits:
1 Remove the ANTENNA-TCAS, BOTTOM [7SG2] AMM 34-43-11-000-001.

Disconnect coaxial cable J3 from the TCAS bottom antenna (7SG2).
Do a check of the connector for moisture:
- If there is moisture, dry and clean the connector.
Do a check of the resistance of the TCAS bottom-antenna connector (33200 ohms +/- 3320 ohms).

2 If the resistance value is in the specified limits:

3 If the resistance value is out of the specified limits:

Subtask 34-43-00-740-073-A

B. Do the test given in Para. 3.

[Rev.8 from Aug 2018] 2026.04.04 04:33:12 UTC