ILS 1 Frequency cannot be tuned

TASK 34-36-00-810-828-A
ILS 1 Frequency cannot be tuned

1. Possible Causes

FMGC-1 [1CA1]
wiring of the FMGC OWN CB1 bus from the FMGC1 (1CA1) to the first terminal block
RMP-COM/NAV FREQ SEL, 1 [1RG1]
wiring of the DATA FROM FMGC bus from the COM/NAV FREQ SEL RMP 1 (1RG1) to the first terminal block
wiring of the NAV FREQ DATA OUTPUT bus from the COM/NAV FREQ SEL RMP 1 (1RG1) to the first terminal block
MMR-1 [40RT1]
wiring of the FREQ/FUNCT SEL SYS PORT A bus from the MMR1 (40RT1) to the first terminal block

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 22-83-34-000-001	Removal of the FMGC
AMM 22-83-34-400-001	Installation of the FMGC
ASM 228602
ASM 231301
AMM 23-13-13-000-001	Removal of the Radio Management Panel (RMP)
AMM 23-13-13-400-001	Installation of the Radio Management Panel (RMP)
AMM 34-14-00-740-001	Interface Test of the IR
AMM 34-36-00-740-003	BITE Test of the MMR
ASM 343601
AMM 34-36-31-000-001	Removal of the ILS Receiver
AMM 34-36-31-400-001	Installation of the ILS Receiver
AMM 34-55-00-740-002	BITE Test of the VOR/MKR

3. Fault Confirmation
Subtask 34-36-00-740-080-B

A. Test
Do the BITE test of the MMR1 AMM 34-36-00-740-003.

4. Fault Isolation
Subtask 34-36-00-810-081-C

A. If the test gives the maintenance message FMGC1(1CA1)/RMP1(1RG1)/MMR1(40RT1):

on the center pedestal, on the RMP1, push the NAV and the ILS pushbutton switches (the green LED on these pushbutton switches comes on).
do the BITE test of the MMR1 AMM 34-36-00-740-003.

(1) If the test does not give the maintenance message
FMGC1(1CA1)/RMP1(1RG1)/MMR1(40RT1):

(a) If the Interface test of the IR gives the maintenance message
FMGC1(1CA1)/ADIRU1(1FP1):

1 If the fault continues:

do a check and repair the wiring of the FMGC OWN CB1 bus from the FMGC1 (1CA1) to the first terminal block ASM 228602.

(b) If the Interface test of the IR does not give the maintenance message
FMGC1(1CA1)/ADIRU1(1FP1):

replace the RMP-COM/NAV FREQ SEL, 1 [1RG1] AMM 23-13-13-000-001 and AMM 23-13-13-400-001.

1 If the fault continues:

do a check and repair the wiring of the DATA FROM FMGC bus from the COM/NAV FREQ SEL RMP 1 (1RG1) to the first terminal block ASM 231301.

(2) If the test gives again the maintenance message
FMGC1(1CA1)/RMP1(1RG1)/MMR1(40RT1):

(a) If the BITE test gives the maintenance message
VOR 1 : NO DATA FROM CONTROL SOURCE:

replace the RMP-COM/NAV FREQ SEL, 1 [1RG1] AMM 23-13-13-000-001 and AMM 23-13-13-400-001.

1 If the fault continues:

do a check and repair the wiring of the NAV FREQ DATA OUTPUT bus from the COM/NAV FREQ SEL RMP 1 (1RG1) to the first terminal block ASM 343601.

(b) If the BITE test does not give the maintenance message
VOR 1 : NO DATA FROM CONTROL SOURCE:

1 If the fault continues:

do a check and repair the wiring of the FREQ/FUNCT SEL SYS PORT A bus from the MMR1 (40RT1) to the first terminal block for pins AB/1C, 1D of the MMR1 ASM 343601.

Subtask 34-36-00-740-081-A

B. Do the test given in Para. 3.

[Rev.8 from Aug 2018] 2026.04.04 04:32:59 UTC