Loss of the GND/FLT Information (PHC 1)

TASK 30-31-00-810-803-A
Loss of the GND/FLT Information (PHC 1)

1. Possible Causes

PROX SNSR-L L/G EXT, SYS 1 [21GA]
PROX SNSR-L L/G EXT, SYS 2 [23GA]
LGCIU-1 [5GA1]
C/B-L/G/LGCIU/SYS1/NORM [1GA]
C/B-HYDRAULIC/LGCIU/SYS2 [2GA]
C/B-HYDRAULIC/LGCIU/SYS1/GRND SPLY [52GA]
PHC-1 [6DA1]
LGCIU-2 [5GA2]
wiring
ADIRU-1 [1FP1]

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 30-31-00-710-001	Operational Test of the Probe Ice Protection
ASM 303101
AMM 30-31-34-000-002	Removal of the Probe Heat Computer (PHC)
AMM 30-31-34-400-002	Installation of the Probe Heat Computer (PHC)
AMM 32-00-00-860-001	Flight Configuration Precautions with Electrical Power
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 32-31-73-200-001	Inspection of the MLG Proximity Sensor and Target Clearances
AMM 32-31-73-400-001	Installation of the MLG Proximity-Sensors
AMM 34-12-34-000-001	Removal of the ADIRU
AMM 34-12-34-400-001	Installation of the ADIRU

3. Fault Confirmation
Subtask 30-31-00-710-054-A

A. Test
(1) Do the operational test of the probe ice protection AMM 30-31-00-710-001.

4. Fault Isolation
Subtask 30-31-00-810-052-A

A. If the ECAM warning message ANTI ICE CAPT PITOT comes into view only or associated with the maintenance message CHECK LGCIU - PHC1 INTERFACE and if the loss of the GND/FLT information occurred:

make sure that there is no maintenance message related to the landing gear system (Ref. ATA 32).

(1) If there is one or more maintenance message(s):

do the related trouble shooting.

(2) If there is no maintenance message:

do the inspection of the MLG proximity sensor and target clearances AMM 32-31-73-200-001.

(a) If the fault continues:

replace the PROX SNSR-L L/G EXT, SYS 1 [21GA] and PROX SNSR-L L/G EXT, SYS 2 [23GA] , AMM 32-31-73-000-001 and AMM 32-31-73-400-001.

(b) If the fault continues:

do a check for ground signal at pin A/<E and/or pin A/<D and/or pin A/<I of the PHC1 (6DA1).

1 If there is no ground signal:

replace the LGCIU-1 [5GA1] AMM 32-31-71-000-001 and AMM 32-31-71-400-001.

2 If there is a ground signal:
Simulate the flight configuration:

on the panel 49VU, open the C/B-L/G/LGCIU/SYS1/NORM [1GA] circuit breaker
on the panel 121VU, open the C/B-HYDRAULIC/LGCIU/SYS2 [2GA] and C/B-HYDRAULIC/LGCIU/SYS1/GRND SPLY [52GA] circuit breakers.

NOTE: Make sure that you obey the flight configuration precautions AMM 32-00-00-860-001.

do a check for ground signal at pin A/<E and/or pin A/<D and/or pin A/<I of the PHC1 (6DA1).

a If there is a ground signal:

replace the LGCIU-1 [5GA1] AMM 32-31-71-000-001 and AMM 32-31-71-400-001.

b If there is no ground signal:

replace the PHC-1 [6DA1] AMM 30-31-34-000-002 and AMM 30-31-34-400-002.

c If the fault continues:

replace the LGCIU-2 [5GA2] .
* If the fault continues:
do a check and repair the wiring from the PHC 1 (6DA1) pin A/<E to the LGCIU 1 (5GA1) pin AB/14A and/or from the PHC 1 pin A/<D to the LGCIU 2 (5GA2) pin AB/14A ASM 303101.

d If the fault continues:

replace the ADIRU-1 [1FP1] AMM 34-12-34-000-001 and AMM 34-12-34-400-001.

Subtask 30-31-00-710-055-A

B. Do the test given in Para. 3.

[Rev.8 from Aug 2018] 2026.04.04 04:29:34 UTC