Loss of the Audio Signal from the VOR Receiver of the VOR/MKR Receiver 1

TASK 34-55-00-810-825-A
Loss of the Audio Signal from the VOR Receiver of the VOR/MKR Receiver 1

1. Possible Causes

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
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)
AMM 34-55-00-710-001	Operational Test of the VOR/MKR
AMM 34-55-00-740-002	BITE Test of the VOR/MKR
ASM 345501
AMM 34-55-31-000-001	Removal of the VOR/MKR Receiver
AMM 34-55-31-400-001	Installation of the VOR/MKR Receiver

3. Fault Confirmation
Subtask 34-55-00-710-054-A

A. Test
Do the operational test of the VOR (system 1) AMM 34-55-00-710-001.

4. Fault Isolation
Subtask 34-55-00-810-086-A

A. If there is no audio signal on the loud speakers during the test when the VOR1 data are shown on the ND:

(1) If the test gives the maintenance message AMU(1RN)/VOR1(3RS1):

(a) If the fault continues:

1 If the fault continues:

remove the VOR/MKR receiver 1
remove the AMU
do a check and repair the wiring from the VOR/MKR receiver 1 to the AMU: from pins AB/7B, 7C to pins AA/8B, 8A ASM 345501
install the VOR/MKR receiver 1
install the AMU.

Subtask 34-55-00-710-055-A

B. Do the test given in Para. 3.

[Rev.8 from Aug 2018] 2026.04.04 04:33:32 UTC