Loss of the Frequency Control by the ATSU on the RMP1

TASK 46-21-00-810-831-A
Loss of the Frequency Control by the ATSU on the RMP1

1. Possible Causes

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 23-13-13-000-001	Removal of the Radio Management Panel (RMP)
AMM 46-21-00-710-001	Operational Test of the ATSU
ASM 462104

3. Fault Confirmation
Subtask 46-21-00-740-108-A

A. Test
(1) Do the fifth part of the operational test of the ATSU AMM 46-21-00-710-001.

4. Fault Isolation
Subtask 46-21-00-810-079-A

A. If during the operational test, the ATSU cannot control the VHF3 frequency through the RMP1 only:

replace the RMP-COM/NAV FREQ SEL, 1 [1RG1] AMM 23-13-13-000-001 and AMM 23-13-13-000-001.

(1) If the fault continues:

repair the wiring of the DFS PORT SELECT DISCRETE from the RMP1 (1RG1) pin A/F to the first terminal block ASM 462104.

Subtask 46-21-00-740-109-A

B. Do the test given in Para. 3.

[Rev.8 from Aug 2018] 2026.04.04 04:34:20 UTC