W DOC AIRBUS | TSM A320F

DEFUEL/XFR/OPEN Lamp - Not On During LTS Test

TASK 28-25-00-810-815-A
DEFUEL/XFR/OPEN Lamp - Not On During LTS Test

WARNING: OBEY THE FUEL SAFETY PROCEDURES.
1. Possible Causes
  • lamp
  • CTL PNL-REFUEL/DEFUEL [800VU]
  • ANN LT-DEFUEL/XFR/OPEN [21QU]
  • diode between pins 7 and 8 (part of diode module 4001VD)
2. Job Set-up Information
 A. Fixtures, Tools, Test and Support Equipment
REFERENCE
QTY
DESIGNATION
No specific
AR
MULTIMETER - STANDARD
 B. Referenced Information
REFERENCE
DESIGNATION
TSM TASK 28-25-00-810-805-A
Refuel/Defuel Floodlight Failure
AMM 28-25-00-710-002
Operational Test of the Defuel System
ASM 282501
ASM 282503
AMM 28-25-55-000-001
Removal of the Refuel Panel
AMM 28-25-55-400-001
Installation of the Refuel Panel
3. Fault Confirmation
Subtask 28-25-00-865-050-A
A. Table of the circuit breakers used in this procedure:
PANELDESIGNATIONFINLOCATION
** ON A/C ALL
121VUFUEL/RFL/DFL/SPLY2QUL24
Subtask 28-25-00-710-064-A
B. Test
   (1) Do Para. 1, 2 and 3 of the Operational Test of the Defuel System AMM 28-25-00-710-002.
NOTE: The HI LVL lights come on during the time the TEST switch is held at LTS.
The HI LVL lights:
  • 28VDC supply is from a different C/B
  • switched ground uses the same contacts of the SWITCH-TEST/HIGH/LTS (2QJ).
   (2) If the DEFUEL/XFR/OPEN lamp (21QU):
     (a) Operates as specified during the test, no trouble-shooting steps are necessary.
     (b) Does not operate during the test, go to Para. 4.
4. Fault Isolation
Subtask 28-25-00-810-064-A
A. Procedure
   (1) Do a check of the FLOODLIGHT-REFUEL/DEFUEL CTL PNL (32QU) to see if it is on.
NOTE: The floodlight 32QU is supplied from the same C/B, 2QU and the same cable routing.
   (2) If the FLOODLIGHT-REFUEL/DEFUEL CTL PNL (32QU) is off, do Refuel/Defuel Floodlight Failure (Ref. TSM TASK 28-25-00-810-805).
   (3) If the FLOODLIGHT-REFUEL/DEFUEL CTL PNL (32QU) is on, keep the TEST switch at LTS and continue the procedure.
   (4) If the HI LVL lights are off:
     (a) Disconnect the end connector 4024VC-A from the CTL PNL-REFUEL/DEFUEL (800VU) AMM 28-25-55-000-001.
     (b) Use a multimeter to do a continuity test, to make sure that a ground is available at the end connector 4024VC-A, pin <J ASM 282501.
     (c) Repair all the unserviceable wiring and connectors.
     (d) Connect the end connector 4024VC-A.
     (e) Do/repeat step (3).
   (5) If the HI LVL lights are on, do a check of and replace, if necessary, the lamp (filament/bulb) of DEFUEL/XFR/OPEN lamp (21QU).
   (6) If the fault continues:
     (a) Remove the CTL PNL-REFUEL/DEFUEL (800VU) AMM 28-25-55-000-001.
     (b) Use a MULTIMETER - STANDARD to do a test, to make sure that 28VDC is available between the end connector 4023VC-A, pin Y (+ve) and 4024VC-A, pin <J.
     (c) If the 28VDC supply volage is correct, replace the CTL PNL-REFUEL/DEFUEL [800VU] AMM 28-25-55-000-001 and AMM 28-25-55-400-001.
NOTE: If due to airline operational conditions it is not possible to replace the CTL PNL-REFUEL/DEFUEL (800VU) and internal trouble-shooting is required, go to step (7).
   (7) Do a check of and replace, if necessary:
     (a) The ANN LT-DEFUEL/XFR/OPEN [21QU]
     (b) The diode between pins 7 and 8 (part of diode module 4001VD).
   (8) Do a check of the CTL PNL-REFUEL/DEFUEL (800VU) wiring ASM 282501 and ASM 282503 between the connectors and components, as shown in the table that follows:
NOTE: The circuit connections shown in the table are abbreviated, for example:
  • the connector 4023VC, pin Y is shown as 4023VC-Y
  • the switch 2QJ, terminal 3A is shown as 2QJ-3A
  • the terminal block 4001VT, terminal 1G is shown as 4001VT-1G
  • the diode module 4001VD, terminal 8 is shown as 4001VD-8.
-----------------------------------------------------------------------------
! CONNECTOR-PIN ! COMPONENT TO COMPONENT ! CONNECTOR-PIN !
!-----------------------------------------------------------------------------!
! 4023VC-Y ---------------------------------------- 4001VT-1G !
! 4001VT-1H ---------------------- 21QU-4 !
! 21QU-5 ------------------------- 21QU-III !
! 21QU-III ----------------------- 21QU-I !
! 21QU-I ------------------------- 21QU-II !
! 21QU-II ------------------------ 4001VT-5A !
! 4001VT-5B ---------------------- 4001VD-7 !
! 4001VD-8 ----------------------- 4001VT-4C !
! 4001VT-4B ---------------------- 2QJ-3A !
! 2QJ-1A ------------------------------------- 4024VC-<J !
-----------------------------------------------------------------------------

     (a) Repair all the unserviceable wiring and connectors.
     (b) Do the test given in Para. 3.B.
[Rev.8 from Aug 2018] 2026.04.04 04:28:46 UTC
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