Access to the RAD/NAV Page on the MCDU 1 Inoperative

TASK 22-82-00-810-821-A
Access to the RAD/NAV Page on the MCDU 1 Inoperative

1. Possible Causes

FMGC-1 [1CA1]
wiring of the NAV CONTROL OWN and NAV CONTROL OPP discretes (from the FMGC 1 (1CA1) 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 228504
AMM 24-41-00-861-002	Energize the Aircraft Electrical Circuits from the External Power
AMM 24-41-00-862-002	De-energize the Aircraft Electrical Circuits Supplied from the External Power

3. Fault Confirmation
Subtask 22-82-00-860-062-A

A. Job Set-up
(1) Aircraft Maintenance Configuration
(a) Energize the aircraft electrical circuits
AMM 24-41-00-861-002.

Subtask 22-82-00-865-056-A

B. Make sure that this(these) circuit breaker(s) is(are) closed:

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C ALL
49VU	AUTO FLT/FMGC/1	10CA1	B02
49VU	AUTO FLT/MCDU/1	11CA1	B01
49VU	COM/RMP/1	2RG1	G10
121VU	COM NAV/RMP/2	2RG2	L02
121VU	AUTO FLT/FMGC/2	10CA2	M17
121VU	AUTO FLT/MCDU/2	11CA2	N20

Subtask 22-82-00-710-090-A

C. Test

ACTION	RESULT
1.On the center pedestal, on the MCDU 1:
turn the BRT knob to make the light more or less bright
push the RAD/NAV mode key.	the RAD/NAV page comes into view.

4. Fault Isolation
Subtask 22-82-00-810-078-A

A. If the RAD/NAV page does not come into view:

(1) If the fault continues:

do a check and repair the wiring of the NAV CONTROL OWN and NAV CONTROL OPP discretes (from the FMGC 1 (1CA1) to the first terminal block) ASM 228504.

Subtask 22-82-00-710-091-A

B. Do the test given in Para. 3.

5. Close-up
Subtask 22-82-00-860-067-A

A. Put the aircraft back to its initial configuration.
(1) De-energize the aircraft electrical circuits
AMM 24-41-00-862-002.

[Rev.8 from Aug 2018] 2026.04.04 04:25:28 UTC