W DOC AIRBUS | TSM A320F

CTR HI LVL Indicator Lamp Does Not Come On When TEST Switch Set To LTS

TASK 28-46-00-810-822-A
CTR HI LVL Indicator Lamp Does Not Come On When TEST Switch Set To LTS

WARNING: OBEY THE FUEL SAFETY PROCEDURES.
1. Possible Causes
  • lamp
  • CTL PNL-REFUEL/DEFUEL [800VU]
  • C/B-FUEL/HI/LVL/SPLY [1QJ]
  • aircraft wiring
  • SWITCH-TEST/HIGH/LTS (2QJ) (part of 800VU)
  • diode module (4002VD) (part of 800VU)
  • INDICATOR-HI LVL/CTR (5QJ) (part of 800VU)
  • Panel Assy-Refuel (800VU) internal wiring
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
AMM 28-25-55-000-001
Removal of the Refuel Panel
AMM 28-25-55-400-001
Installation of the Refuel Panel
AMM 28-46-00-710-001
Test of the Tank High-Level Sensing-System
AWM 284601
AWM 284602
AWM 284603
3. Fault Confirmation
Subtask 28-46-00-710-053-B
A. Do up to and including Para. 3.A. of the Operational Test of the HI LVL Lights AMM 28-46-00-710-001.
NOTE: The OPEN DEFUEL/XFR lamp (21QU) should also come on during the time the TEST switch is held at LTS.
The OPEN DEFUEL/XFR indicator lamp (21QU):
  • 28VDC supply is from a different C/B
  • switched ground/earth uses the same contacts of SWITCH-TEST/HIGH/LTS (2QJ).
4. Fault Isolation
Subtask 28-46-00-810-071-B
A. If the CTR HI LVL indicator lamp only does not come on and the others do:
  • replace the CTR HI LVL indicator lamp bulb.

    OR

    If at least one HI LVL indicator lamp comes on but others do not:
  • replace the related lamps.
   (1) If the fault continues or if none of the Panel Assy-Refuel (800VU) HI LVL indicator lamps come on:
     (a) Remove the Panel Assy-Refuel (800VU) AMM 28-25-55-000-001.
     (b) Do a check AWM 284601, and AWM 284602 with a MULTIMETER - STANDARD to see if:
       1 28VDC is available at the aircraft connector 4023VC pin <C.
       2 A ground/earth is available at the aircraft connector 4024VC pin <J.
   (2) If 28VDC and the ground/earth is available at the aircraft connectors as specified above:
NOTE: If due to airline operational conditions it is not possible to replace the Panel Assy-Refuel (800VU) and internal Trouble-shooting is required, go to Step (8).
   (3) If 28VDC is not available in Step (1)(b)1_:
  • check/reset/replace the C/B-FUEL/HI/LVL/SPLY [1QJ] at 121VU212.
   (4) Do the test given in Para. 3.A.
   (5) If the fault continues do a check AWM 284601, and AWM 284602 of the aircraft wiring :
  • between the C/B-FUEL/HI/LVL/SPLY (1QJ) and the refuel panel connector 4023VC pin <C
  • between the DC1 ground point and the refuel panel connector 4024VC pin <J.
   (6) Repair all the unserviceable wiring and connectors.
   (7) Do the test given in Para. 3.A.
   (8) Panel Assy-Refuel (800VU) Internal Trouble-shooting, AWM 284602, and AWM 284603:
     (a) Check/replace the SWITCH-TEST/HIGH/LTS (2QJ) (part of 800VU).
     (b) Check/replace the diode between terminals 5 and 6 of diode module (4002VD) (part of 800VU).
     (c) Check/replace the INDICATOR-HI LVL/CTR (5QJ) (part of 800VU).
     (d) Check/repair the Panel Assy-Refuel (800VU) internal wiring as follows:
  • connector 4023VC, pin <C to terminal block 4001VT, terminal 5C
  • terminal block 4001VT, terminal 5H to IND-HI LVL/CTR (5QJ), terminal 4
  • IND-HI LVL/CTR (5QJ), terminal 5 loop connection to terminals III, II, and I
  • IND-HI LVL/CTR (5QJ), terminal I to terminal block 4001VT, terminal 4A
  • terminal block 4001VT, terminal 4F to diode module 4002VD, terminal 5
  • diode module 4002VD, terminal 6 to terminal block 4001VT, terminal 4E
  • terminal block 4001VT, terminal 4B to SW-TEST/HI/LIGHTS (2QJ), terminal 3A
  • SW-TEST/HI/LIGHTS (2QJ), terminal 1A to connector 4024VC, pin <J.
     (e) Install the Panel Assy-Refuel (800VU), AMM 28-25-55-400-001.
     (f) Do the test given in Para. 3.A.
[Rev.8 from Aug 2018] 2026.04.04 04:39:43 UTC
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