Wing Anti-Ice Control-Valves Stay Open After Ground Test

TASK 30-11-00-810-808-A
Wing Anti-Ice Control-Valves Stay Open After Ground Test

WARNING: DO NOT TOUCH THE ANTI-ICE DUCTS UNTIL THEY ARE COOL. THE TEMPERATURE OF THE DUCTS STAYS HIGH FOR SOME TIME AFTER THE ENGINE STOPS.

1. Possible Causes

RELAY-GROUND TEST [4DL]
LGCIU-1 [5GA1]
LGCIU-2 [5GA2]
PROX SNSR-L L/G EXT, SYS 1 [21GA]
PROX SNSR-R L/G EXT, SYS 2 [22GA]
aircraft wiring
RELAY-FAULT MONITOR C/O [6DL]

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 30-11-00-710-001	Operational Test of the Wing Ice-Protection System
ASM 301101
AMM 32-31-71-000-001	Removal of the LGCIU
AMM 32-31-71-400-001	Installation of the LGCIU
AMM 32-31-73-000-001	Removal of the MLG Proximity-Sensors
AMM 32-31-73-400-001	Installation of the MLG Proximity-Sensors
AMM 32-31-73-820-002	Adjustment of the MLG Extension Proximity Sensors

3. Fault Confirmation
Subtask 30-11-00-710-055-A

CAUTION: MAKE SURE THAT YOU SET THE WING ANTI-ICE SYSTEM P/BSW TO OFF AFTER 30 SECONDS. THIS WILL PREVENT DAMAGE TO THE SLATS.

A. Procedure

NOTE: When the Wing Anti-Ice System Ground Test is OK, the system will automatically switch off after 30 seconds. If after 35 seconds the anti-ice symbols on the BLEED page, on the lower ECAM DU, do not go off, the ANTI ICE WING P/BSW must be released (out) manually.

(1) If the ECAM message WING A.-ICE OPEN ON GND is shown:
(a) Do the operational test of the wing anti-ice system. AMM 30-11-00-710-001:

if the test is OK, no more maintenance work is necessary
if the test is not OK, do the fault isolation procedure in Para. 4.A.

4. Fault Isolation
Subtask 30-11-00-810-055-A

A. Procedure
(1) Replace the RELAY-GROUND TEST [4DL] .
(a) Do the test in Para. 3.A.:

if the fault continues do the next step.

NOTE: When the Anti-Ice Ground Test is done two or more times, keep sufficient time between each test, to let the slats become cool.

(2) Remove the RELAY-GROUND TEST 4DL and RELAY-FAULT MONITOR C/O 6DL from their holders.

NOTE: When the RELAY-GROUND TEST 4DL is removed from its holder, this will remove the ground from pin Z of the RELAY-FAULT MONITOR C/O 6DL.

(3) At pin Z of the Relay 6DL holder, do a check for continuity to ground:

if there is no ground, do step (10)
if there is a ground, do the next step.

(4) Remove each LGCIU from its ARINC tray AMM 32-31-71-000-001 in sequence until the ground goes from pin Z of relay 6DL:

if the ground on pin Z stays when both the LGCIUs have been removed, do step (9)
if the ground on pin Z goes when an LGCIU is removed, do the next step.

(5) Interchange and install the two LGCIUs AMM 32-31-71-400-001, and do steps (3) thru (4) again:

if the ground on pin Z goes when the LGCIU is removed from the same system as in step (4), install the LGCIUs and relays 4DL and 6DL, and do step (7)
if the ground on pin Z goes when the LGCIU is removed from the opposite system to that in step (4), install the LGCIUs and relays 4DL and 6DL, and do the next step.

(6) Replace the LGCIU-1 [5GA1] or LGCIU-2 [5GA2] in the system which had the ground in step (5), AMM 32-31-71-000-001 and AMM 32-31-71-400-001.
(a) Do the test in Para 3.A.:

if the fault continues, do the next step.

(7) Adjust the applicable prox sensor PROX SNSR-L L/G EXT, SYS 1 [21GA] or PROX SNSR-R L/G EXT, SYS 2 [22GA] AMM 32-31-73-820-002, related to the LGCIU which gave the ground:

for LGCIU1 adjust proximity sensor 21GA
for LGCIU2 adjust proximity sensor 22GA.

(a) Do the test in Para. 3.A.:

if the fault continues, do the next step.

(8) Replace the unserviceable proximity sensor AMM 32-31-73-000-001 and AMM 32-31-73-400-001.
(a) Do the test in Para. 3.A.:

if the fault continues, do the next step.

(9) Do a check and repair as necessary the aircraft wiring ASM 301101 between pin Z of relay 6DL and:

the RELAY-GROUND TEST 4DL
the RELAY-ANTI ICE VALVE CONTROL 5DL
the LGCIU1 5GA1
the LGCIU2 5GA2

(a) Do the test in Para. 3.A.:

if the fault continues, do the next step.

(10) Replace the RELAY-FAULT MONITOR C/O [6DL] .
(a) Do the test in Para. 3.A.

[Rev.8 from Aug 2018] 2026.04.04 04:29:30 UTC