A/THR Engagement Inoperative on the FMGC 2

TASK 22-31-00-810-806-A
A/THR Engagement Inoperative on the FMGC 2

1. Possible Causes

FMGC-2 [1CA2]
FCU [2CA]
wiring of the A/THR 2 SW COM and A/THR 2 SW MON discretes (from the FCU (2CA) to the FMGC 2 (1CA2))

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
ASM 223101
AMM 22-81-12-000-001	Removal of the FCU
AMM 22-81-12-400-001	Installation of the FCU
AMM 22-83-34-000-001	Removal of the FMGC
AMM 22-83-34-400-001	Installation of the FMGC
AMM 22-96-00-710-001	Operational Test of the AFS

3. Fault Confirmation
Subtask 22-31-00-710-060-A

A. Test
(1) On the FCU, push the A/THR pushbutton switch.
(2) Do the operational test of the AFS AMM 22-96-00-710-001 and read the result for the FMGC 2.

4. Fault Isolation
Subtask 22-31-00-810-055-A

A. If the test gives the maintenance message AFS : FMGC2/FCU (ATHR SW):

replace the FMGC-2 [1CA2] AMM 22-83-34-000-001 and AMM 22-83-34-400-001.

(1) If the fault continues:

replace the FCU [2CA] AMM 22-81-12-000-001 and AMM 22-81-12-400-001.

(2) If the fault continues:

do a check and repair the wiring of the A/THR 2 SW COM and A/THR 2 SW MON discretes (from the FCU (2CA) to the FMGC 2 (1CA2)) ASM 223101.

Subtask 22-31-00-710-061-A

B. Do the test given in Para. 3.

[Rev.8 from Aug 2018] 2026.04.04 04:25:09 UTC