(4) On the sensor do a check of circuit isolation:

 (a) Connect the pins A and B together.

 (b) Connect one test lead of the 50Vdc Isolation Tester to the pins AB and the other test lead to the case.

 (c) Supply a test signal for 5 seconds and read the resistance value shown

 (d) The resistance value must be more than 400Megohms.

 (5) If the (20GA) (22GA) fails one of the two (2) test at Para. 4.A.(3) or (4) replace the unserviceable proximity sensor (Ref. AMM TASK 32-31-73-000-001) (Ref. AMM TASK 32-31-73-400-001).

 「一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一1 EFF : ALL ∞∞32-31-00∞∞∞∞∞∞∞∞∞∞Page 225
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 (6) If the tests at Para. 4.A.(3) and (4) are satisfactory then do a check of the Aircraft Wiring between the PROX SNSR 20GA (22GA) electrical connector and LGCIU-1 (2) ARINC tray (Ref. ASM 323103S01) (Ref. ASM 323104S01).

 (7) If there is a circuit/interface fault do the repair.

 (8) Do the L/G BITE test as in Para. 3.A.(1).

 (9) If no fault is found at Para. 4.A.(6), replace the LGCIU-1 (5GA1) or LGCIU-2 (5GA2) (Ref. AMM TASK 32-31-71-000-001) (Ref. AMM TASK 32-31-71-400-001).

 (10) Do the GROUND SCANNING and make sure that the ground log is clear.
 5. Close-up
________
 A. Put the aircraft back to its initial configuration.
 「一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一1 EFF : ALL ∞∞32-31-00∞∞∞∞∞∞∞∞∞∞Page 226
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 TASK 32-31-00-810-814

 L MLG Compressed/Extended Proximity Sensor Failed to Flight Condition (21GA, 23GA)
 WARNING : MAKE SURE THAT THE GROUND SAFETY-LOCKS ARE IN POSITION ON THE LANDING
_______ GEAR.
 1. Possible Causes
_______________
 - LGCIU-1 (5GA1)

 - LGCIU-2 (5GA2)

 - proximity sensor 21GA

 - proximity sensor (23GA)

 - aircraft wiring

 2. Job Set-up Information
______________________
 A. Fixtures, Tools, Test and Support Equipment
 -------------------------------------------------------------------------------REFERENCE QTY DESIGNATION -------------------------------------------------------------------------------
No specific Multimeter No specific 50Vdc Isolation Tester
 B. Referenced Information
 -------------------------------------------------------------------------------REFERENCE DESIGNATION
 -------------------------------------------------------------------------------
ASM 323103S01
 ASM 323104S01
 AMM 32-31-71-000-001 Removal of the LGCIU (5GA1, 5GA2)
 AMM 32-31-71-400-001 Installation of the LGCIU (5GA1, 5GA2)
 AMM 32-31-73-000-001 Removal of the Proximity-Sensors 9GA(8GA),

 11GA(10GA), 27GA(26GA), 29GA(28GA), 15GA(14GA), 17GA(16GA), 21GA(20GA), 23GA(22GA), 33GA(32GA), 35GA(34GA)
 AMM 32-31-73-400-001  Installation of the Proximity-Sensors 9GA(8GA), 11GA(10GA), 27GA(26GA), 29GA(28GA), 15GA(14GA), 17GA(16GA), 21GA(20GA), 23GA(22GA), 33GA(32GA)...
 AMM 32-69-00-740-001  BITE Check Landing Gear Control Interface Unit (LGCIU) using MCDU to Ensure that Continuous BITE is Operative
 「一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一一1 EFF : ALL ∞∞32-31-00∞∞∞∞∞∞∞∞∞∞Page 227
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 3. Fault Confirmation
__________________

 A. This fault condition causes the "Knock On Faults" to the LRUs as listed in the Table 2 of Page Block 301.
 (1) Do a BITE test on the LGCIU-1 (2) (Ref. AMM TASK 32-69-00-740-001)

 (2) Access LGCIU-1 (2) TROUBLE SHOOTING (ground) and read the BITE test fault number(s), for fault confirmation (refer to AMM 326900 table 4).

 NOTE : The table 4 shows the fault messages approximate to the CFDS
____
 message

 (3) Do the fault isolation.
 4. Fault Isolation
_______________
 A. Procedure.
 (1) Refer to (Ref. AMM TASK 32-31-73-000-001) Figure 404/TASK 32-31-73-991-004, and find the applicable proximity sensor 21GA proximity sensor (23GA).

 (2) Release the electrical connector of the BITE shown failed proximity sensor.

 NOTE : If the ELDEC proximity sensor test unit is available, go to
____ page block 301 and do the procedure in table 5.
 (3) Use a Multimeter and do a check of the resistance between the pins A and B of the proximity sensor, (Ref. ASM 323103S01) (Ref. ASM 323104S01) the resistance must be approximately 13ohms.
　
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本文鏈接地址：A320 Trouble Shooting Manual 排故手冊 起落架 LANDING GEAR 1(13)