Loss of the VHF 1 Reception

TASK 23-12-00-810-814-A
Loss of the VHF 1 Reception

1. Possible Causes

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 23-12-00-710-001	Operational Test of the VHF System
AMM 23-12-33-000-001	Removal of the VHF Transceiver
AMM 23-12-33-400-001	Installation of the VHF Transceiver
ASM 235106
AMM 23-51-34-000-001	Removal of the Audio Management Unit (AMU) (1RN)
AMM 23-51-34-400-001	Installation of the Audio Management Unit (AMU) (1RN)

3. Fault Confirmation
Subtask 23-12-00-710-058-A

A. Test
(1) Do the operational test of the VHF system AMM 23-12-00-710-001.

NOTE: Do this test for the VHF 1 system only.

4. Fault Isolation
Subtask 23-12-00-810-069-A

A. If the reception function is not possible during the operational test of the VHF 1 system:

(1) If the fault continues:

(a) If the fault continues:

do a check and repair the wiring from VHF 1 transceiver (1RC1) to AMU (1RN) of the AUDIO SIDETONE OUTPUT signal, from pins AB/15A, 15B to pins AA/1A, 1B ASM 235106.

Subtask 23-12-00-710-059-A

B. Do the test given in Para. 3.

[Rev.8 from Aug 2018] 2026.04.04 04:38:57 UTC