RLG Uplock Proximity Sensor Fault (8GA, 10GA)

TASK 32-31-00-810-825-A
RLG Uplock Proximity Sensor Fault (8GA, 10GA)

WARNING: MAKE SURE THAT THE GROUND SAFETY-LOCKS ARE IN POSITION ON THE LANDING GEAR. MOVEMENT OF THE LANDING GEAR CAN CAUSE INJURY TO PERSONS AND DAMAGE TO THE AIRCRAFT AND/OR EQUIPMENT.

WARNING: PUT THE SAFETY DEVICES AND THE WARNING NOTICES IN POSITION BEFORE YOU START A TASK ON OR NEAR:

THE FLIGHT CONTROLS
THE FLIGHT CONTROL SURFACES
THE LANDING GEAR AND THE RELATED DOORS
COMPONENTS THAT MOVE.

MOVEMENT OF COMPONENTS CAN KILL OR CAUSE INJURY TO PERSONS AND/OR CAN CAUSE DAMAGE TO THE EQUIPMENT.

1. Possible Causes

UPLOCK ASSY-MLG, R [2510GM]
PROX SNSR-R L/G UPLK, SYS 1 [8GA]
PROX SNSR-R L/G UPLK, SYS 2 [10GA]
wiring
LGCIU-1 [5GA1]
LGCIU-2 [5GA2]

2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	AR	MULTIMETER - STANDARD
No specific	AR	TESTER - INSULATION RESISTANCE
38-368-02	1	UNIT-TEST,SENSOR
38-368-03	1	UNIT-TEST,SENSOR

B. Referenced Information

REFERENCE	DESIGNATION
AMM 12-22-32-640-001	Lubrication of Main Landing Gear and Doors
AMM 32-12-00-010-001	Open the Main Gear Doors for Access
AMM 32-31-00-040-003	Check of the System 2 Proximity Sensors of the Landing Gear and the Landing Gear Doors
ASM 323103
ASM 323104
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 32-69-00-740-001	BITE Check of Landing-Gear Control Interface-Unit (LGCIU) With Use of MCDU to Ensure that Continuous BITE is Operative
TSM TASK 32-31-00-03	NORMAL EXTENSION AND RETRACTION - TASK SUPPORTING DATA

3. Fault Confirmation
Subtask 32-31-00-740-065-A

A. Test
(1) Do a BITE test on the LGCIU-1 (2) AMM 32-69-00-740-001:
(a) Access LGCIU-1 (2) TROUBLE SHOOTING (ground) and read the BITE test fault number(s) for fault confirmation (refer to TSM 323100 PB 301).

NOTE: The table shows the CFDS FAULT message.

(2) Do the fault isolation.

4. Fault Isolation
Subtask 32-31-00-810-076-A

A. Procedure
(1) Open the R L/G Door to get access to the proximity sensor(s) AMM 32-12-00-010-001.

NOTE: If the UPLOCK ASSY-MLG, R [2510GM] is incorrectly greased it can cause incorrect operation (Ref. TFU 323144001).

(2) Do a visual inspection of the UPLOCK ASSY-MLG, R [2510GM] and look for signs of overgreasing AMM 12-22-32-640-001.
(3) Refer to AMM 32-31-73-000-001 Figure 401/TASK 32-31-73-991-001 and find the PROX SNSR-R L/G UPLK, SYS 1 [8GA] and the PROX SNSR-R L/G UPLK, SYS 2 [10GA] .
(4) If the BITE test shows a proximity sensor fault, do the steps that follow:
(a) At the applicable proximity sensor, release the electrical-connector.
(b) If the 38-368-02 UNIT-TEST,SENSOR or the 38-368-03 UNIT-TEST,SENSOR is available, do the troubleshooting procedure of the proximity sensor 32-31-00-03 TSM TASK 32-31-00-03.
(5) Use the MULTIMETER - STANDARD and do a check of the resistance between pins A and B of the proximity sensor, ASM 323103 or ASM 323104. Make sure that the resistance is:

Between 11 and 13 ohms for a ferrite proximity sensor (PN 8-484-01)
Between 15 and 17 ohms for an all metal proximity sensor (PN 8-933-01).

(6) On the proximity sensor, do a check of the circuit isolation:
(a) Connect pins A and B together.
(b) Connect one test lead of the TESTER - INSULATION RESISTANCE to pins AB and the other test lead to the case.
(c) Supply a test signal for five seconds and read the resistance value shown.
(d) Make sure that the resistance is more than 400 Megohms.
(7) If one of the two tests at Para. 4.A. (5) and (6) is unsatisfactory for the PROX SNSR-R L/G UPLK, SYS 1 [8GA] or the PROX SNSR-R L/G UPLK, SYS 2 [10GA] :
(a) Replace the unserviceable proximity sensor AMM 32-31-73-000-001 and AMM 32-31-73-400-001.
(8) If the tests at Para. 4.A. (5) and (6) are satisfactory, then:
(a) Do a check of the wiring between the applicable proximity sensor electrical-connector and LGCIU 1 or LGCIU 2 ARINC tray, ASM 323103 or ASM 323104.
(9) If there is a circuit/interface fault, repair it.
(10) Do the L/G BITE test as in Para. 3.A. (1).
(11) If no fault is found at Para. 4.A. (8):
(a) Replace the LGCIU-1 [5GA1] or the LGCIU-2 [5GA2] AMM 32-31-71-000-001 and AMM 32-31-71-400-001.
(12) Do the GROUND SCANNING and make sure that the ground log is clear.
(13) If MMEL conditions apply to the PROX SNSR-R L/G UPLK, SYS 2 [10GA] :
(a) Do the deactivation procedure of the proximity sensor AMM 32-31-00-040-003.

5. Close-up
Subtask 32-31-00-860-075-A

A. Put the aircraft back to its initial configuration.

[Rev.8 from Aug 2018] 2026.04.04 04:31:20 UTC