Slats System 1 (2) Fault with the A-LOCK Flag Shown on the EWD When Retracting the Slats While the Aircraft is on the Ground

TASK 27-81-00-810-839-A
Slats System 1 (2) Fault with the A-LOCK Flag Shown on the EWD When Retracting the Slats While the Aircraft is on the Ground

1. Possible Causes

RELAY-A/C ON GND [94CV]
RELAY-A/C ON GND [96CV]
aircraft wiring

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 27-81-00-740-002	BITE Test of the Slat and Flap Control Computers (Slat System)
ASM 278102
ASM 278103

3. Fault Confirmation
Subtask 27-81-00-710-070-A

A. Test
(1) If the Post Flight Report shows the ECAM message SLAT SYS 1(2) FAULT and the A-LOCK legend (cyan) flashed during slat retraction on the ground, do the next step.
(2) Do a BITE test of the applicable system SFCC slat channel AMM 27-81-00-740-002:

if the test completes, but gives a different maintenance message, do the trouble shooting procedure related to the maintenance message.
if you cannot access the test page, do the fault isolation procedure given in Para. 4.

NOTE: When the aircraft is on the ground, the A-LOCK legend can only show if the SFCC1 or SFCC2 slat channel is incorrectly in the flight mode. The legend will go off when the serviceable channel has fully retracted the slats (at half speed). It is not possible to access the slat test page when the related slat channel is in the flight mode.

4. Fault Isolation
Subtask 27-81-00-810-088-A

A. Procedure
(1) Replace the applicable A/C ON GND relay:

for Slat 1 replace RELAY-A/C ON GND [94CV]
for Slat 2 replace RELAY-A/C ON GND [96CV] .

(2) Do the test given in Para. 3. A. (2):

if the fault continues, do the next step.

(3) Do a check of the aircraft wiring ASM 278102 or ASM 278103 and repair as necessary.
(4) Do the test given in Para. 3. A. (2).

[Rev.8 from Aug 2018] 2026.04.04 04:27:51 UTC