Loss of the ATC Bottom Antenna 1 Signals

TASK 34-52-00-810-803-A
Loss of the ATC Bottom Antenna 1 Signals

1. Possible Causes

XPDR-ATC/MODE S, 1 [1SH1]
wiring from the ATC/MODE S transponder 1 (1SH1) to the ATC bottom antenna 1 (7SH1)
ANTENNA-ATC BOTTOM, 1 [7SH1]

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 34-52-00-740-004	BITE Test of the ATC
ASM 345201
AMM 34-52-11-000-001	Removal of the ATC Antenna
AMM 34-52-11-400-001	Installation of the ATC Antenna
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 34-52-00-740-054-A

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

4. Fault Isolation
Subtask 34-52-00-810-054-B

A. If the BITE test gives the maintenance message ATC1 BOT ANTENNA (7SH1) :

(1) If the fault continues:

do a check of the wiring from the ATC/MODE S transponder 1 (1SH1) to the ATC bottom antenna 1 (7SH1) ASM 345201.

(a) If there is no continuity:

(b) If there is continuity:

Subtask 34-52-00-740-055-A

B. Do the test given in Para. 3.

[Rev.8 from Aug 2018] 2026.04.04 04:33:22 UTC