W DOC AIRBUS | TSM A320F

L(R) Surge Tank Overflow Sensor 28QJ1(2)

TASK 28-46-00-810-812-A
L(R) Surge Tank Overflow Sensor 28QJ1(2)

WARNING: OBEY THE FUEL SAFETY PROCEDURES.
WARNING: WHEN YOU DO WORK ON THE FUEL SYSTEM WIRING, YOU MUST USE TEST EQUIPMENT THAT IS APPROVED (REFER TO INTERNATIONAL OR NATIONAL SPECIFICATIONS FOR INTRINSICALLY SAFE TEST EQUIPMENT: EN50020, UL913 OR EQUIVALENT). TEST EQUIPMENT THAT IS NOT APPROVED CAN CAUSE FIRE OR AN EXPLOSION.
1. Possible Causes
  • FLSCU-1 [7QJ]
  • FLSCU-2 [9QJ]
  • aircraft wiring
  • HARNESS-L VENT SURGE TK [34QJ1]
  • HARNESS-R VENT SURGE TK [34QJ2]
  • SENSOR-HIGH LVL, LEFT WING SURGE TK CHANNEL A [28QJ1]
  • SENSOR-HIGH LVL, RIGHT WING SURGE TK CHANNEL A [28QJ2]
  • CHECK VALVE-FUEL DRAIN, L WING TK INR FWD [50QM]
  • CHECK VALVE-FUEL DRAIN, R WING TK INR FWD [51QM]
  • CHECK VALVE-FUEL DRAIN, L WING TK OUTR [52QM]
  • CHECK VALVE-FUEL DRAIN, R WING TK OUTR [53QM]
  • CHECK VALVE-FUEL DRAIN, L WING TK INR REAR [120QM]
  • CHECK VALVE-FUEL DRAIN, R WING TK INR REAR [121QM]
  • CHECK VALVE-FUEL DRAIN, CTR TK [93QM]
  • VALVE-FLOAT VENT, L WING TK INR [16QM]
  • VALVE-FLOAT VENT, R WING TK INR [17QM]
  • VALVE-FLOAT VENT, L WING TK OUTR [15QM]
  • VALVE-FLOAT VENT, R WING TK OUTR [18QM]
  • vent pipes and structure
2. Job Set-up Information
 A. Referenced Information
REFERENCE
DESIGNATION
TSM TASK 28-46-00-810-818-A
FLSCU1(2) 7QJ(9QJ)
ESPM 2053210
AMM 28-00-00-000-001
Removal of the Fuel Pipes
AMM 28-00-00-400-001
Installation of the Fuel Pipes
AMM 28-10-00-910-001
Safety Procedures When You Do Work in a Fuel Tank
AMM 28-10-00-910-002
Access to the Fuel Tanks and the Work Areas
AMM 28-11-00-280-003
Structural Fuel Leaks - Analysis of the Route, Location of the Source and the Identification of Applicable Leak Tests
AMM 28-12-43-000-001
Removal of the Vent Float-Valve
AMM 28-12-43-000-002
Removal of the Vent Float-Valve
AMM 28-12-43-400-001
Installation of the Vent Float-Valve
AMM 28-12-43-400-002
Installation of the Vent Float-Valve
AMM 28-12-44-000-001
Removal of the Check Valve
AMM 28-12-44-000-002
Removal of the Check Valve
AMM 28-12-44-000-003
Removal of the Check Valve
AMM 28-12-44-000-004
Removal of the Check Valve
AMM 28-12-44-400-001
Installation of the Check Valve
AMM 28-12-44-400-002
Installation of the Check Valve
AMM 28-12-44-400-003
Installation of the Check Valve
AMM 28-12-44-400-004
Installation of the Check Valve
AMM 28-46-00-740-001
Functional (BITE) Test
AWM 284601
ASM 284604
AWM 284606
AWM 284611
AWM 284612
AMM 28-46-16-000-001
Removal of the Overflow Sensor
AMM 28-46-16-400-001
Installation of the Overflow Sensor
AMM 28-46-34-000-001
Removal of the Fuel-Level Sensing Control-Unit (FLSCU)
AMM 28-46-34-400-001
Installation of the Fuel-Level Sensing Control-Unit (FLSCU)
AMM 28-46-43-000-001
Removal of the Vent Surge Tank-Harness
AMM 28-46-43-400-001
Installation of the Vent Surge Tank-Harness
3. Fault Confirmation
Subtask 28-46-00-740-061-A ** ON A/C NOT FOR ALL
A. Test
   (1) Do the BITE test of the FLSS AMM 28-46-00-740-001.
   (2) Examine the FLSS STATUS page on the MCDU.
   (3) If the page shows messages for one or more of the other sensors and/or the FLSCU-1(2), do (Ref. TSM TASK 28-46-00-810-818).
   (4) If the message 284616 L(R) SURGE SENSOR 28QJ1(2):

  • is shown, do Para. 4.A.

  • is not shown, no work steps are necessary.
NOTE: You can get more data from the:
  • Aircraft Maintenance Manual (AMM) Chap. 28-46-00, the Fuel Level Sensing System, Description and Operation (D and O)
  • Trouble Shooting Manual (TSM) - Task Supporting Data (Ref. P. Block 301)
  • Aircraft Schematic Manual (ASM) ASM 284604.
You can get more Trouble-shooting data from the CFDS(FUEL):
  • Input Parameters Page 3 (Ref. P. Block 301)
  • FLSCU Trouble-shooting Data (Ref. P. Block 301).
NOTE: OPTIONAL TESTING:
Where a PSD A320-2 Fuel Level Sensing Test Set is available measurements can be taken before a decision is made to go into or close up a fuel tank. The Test Set enables the tank mounted components and tank wiring to be tested from the tank wall connectors.
Subtask 28-46-00-740-061-C ** ON A/C NOT FOR ALL
A. Test
   (1) Do the BITE test of the FLSS AMM 28-46-00-740-001.
   (2) Examine the FLSS STATUS page on the MCDU.
   (3) If the page shows messages for one or more of the other sensors and/or the FLSCU-1(2), do (Ref. TSM TASK 28-46-00-810-818).
   (4) If the message 284616 L(R) SURGE SENSOR 28QJ1(2):

  • is shown, do Para. 4.A.

  • is not shown, no work steps are necessary.
NOTE: You can get more data from the:
  • Aircraft Maintenance Manual (AMM) Chap. 28-46-00, the Fuel Level Sensing System, Description and Operation (D and O)
  • Trouble Shooting Manual (TSM) - Task Supporting Data (Ref. P. Block 301)
  • Aircraft Schematic Manual (ASM) ASM 284604.
You can get more Trouble-shooting data from the CFDS(FUEL):
  • Input Parameters Page 3 (Ref. P. Block 301)
  • Trouble-shooting Data (Ref. P. Block 301).
NOTE: OPTIONAL TESTING:
Where a PSDA321-1 Test Set is available, a check can be made before a decision is made to go into or close up a fuel tank. The Test Set enables a GO/NOGO check to be made of the tank mounted components and wiring from the tank wall connectors.
4. Fault Isolation
Subtask 28-46-00-810-061-A ** ON A/C NOT FOR ALL
A. Procedure
   (1) Do the steps applicable to the test equipment available.
   (2) Test Equipment.
WARNING: WHEN YOU DO WORK ON THE FUEL SYSTEM WIRING, YOU MUST USE TEST EQUIPMENT THAT IS APPROVED (REFER TO INTERNATIONAL OR NATIONAL SPECIFICATIONS FOR INTRINSICALLY SAFE TEST EQUIPMENT: EN50020, UL913 OR EQUIVALENT). TEST EQUIPMENT THAT IS NOT APPROVED CAN CAUSE FIRE OR AN EXPLOSION.
     (a) If there is:

  • approved test equipment available, go to Step (3)

  • no approved test equipment available, go to Step (6).
   (3) Get access to the tank wall connector 4047VC1(2)-A (for the vent surge tank harness 34QJ1(2)) AMM 28-46-43-000-001.
   (4) Disconnect the free connector 4047VC1(2)-A from the receptacle 4047VC1(2).
   (5) Do a resistance check of the sensor 28QJ1(2) at the tank wall connector 4047VC1(2) between pins A and B AWM 284611 and AWM 284612.
Make sure the resistance is between 330 and 480 ohms.
If there is:

  • continuity as specified above, go to Step (6)

  • no continuity as specified above (resistance check out of range), go to Step (8).
NOTE: The sensor status (wet or dry) and fuel/air temperature will have an effect on the resistance value.
   (6) Replace the FLSCU-1 [7QJ] ( FLSCU-2 [9QJ] ) AMM 28-46-34-000-001 and AMM 28-46-34-400-001.
   (7) If the fault continues:
     (a) Get access to the tank wall connector 4047VC1(2)-A (for the vent surge tank harness 34QJ1(2)) AMM 28-46-43-400-001.
     (b) Disconnect the free connector 4047VC1(2)-A from the receptacle 4047VC1(2).
     (c) Do a check AWM 284611, and AWM 284612 of the aircraft wiring (sensor input line - H) between the FLSCU-1(2) rack connector AB, pin 14A and the tank wall free connector 4047VC1(2)-A, pin A.
     (d) Do a check AWM 284611, and AWM 284612 of the aircraft wiring (sensor input line - L) between the FLSCU-1(2) rack connector AB, pin 14B and the tank wall free connector 4047VC1(2)-A, pin B.
     (e) Do a check AWM 284601 of the aircraft wiring (FLSCU-1 BITE 1 test command line) between the FLSCU-1 rack connector AA, pin 15B and the FQIC rack connector AB, pin 7H or the (aircraft wiring (FLSCU-2 BITE 1 test command line) between the FLSCU-2 rack connector AA, pin 15B and the FQIC rack connector AB, pin 10H).
     (f) Do a check AWM 284606 of the aircraft wiring (FLSCU-1 LS4 output line) between the FLSCU-1 rack connector AB, pin 1B and the FQIC rack connector AB, pin 2K or the (aircraft wiring (FLSCU-2 LS4 output line) between the FLSCU-2 rack connector AB, pin 1B and the FQIC rack connector AB, pin 10K).
     (g) Repair all the unserviceable wiring and connectors ESPM 2053210.
     (h) Connect the free connector 4047VC1(2)-A to the receptacle 4047VC1(2).
     (i) Do the test in Para. 3.A.
   (8) If the fault continues or if there is no continuity in Step (5):
     (a) Drain, open and vent the tank AMM 28-10-00-910-001 and AMM 28-10-00-910-002.
     (b) Do a wiring check of the HARNESS-L VENT SURGE TK [34QJ1] ( HARNESS-R VENT SURGE TK [34QJ2] ) AWM 284611 ( AWM 284612) and replace, if necessary AMM 28-46-43-000-001 and AMM 28-46-43-400-001.
     (c) If the harness is serviceable, replace the SENSOR-HIGH LVL, LEFT WING SURGE TK CHANNEL A [28QJ1] ( SENSOR-HIGH LVL, RIGHT WING SURGE TK CHANNEL A [28QJ2] ) AMM 28-46-16-000-001 and AMM 28-46-16-400-001.
   (9) If the fault continues:
     (a) Get access to the fuel tanks AMM 28-10-00-910-001 and AMM 28-10-00-910-002.
     (b) Do a visual inspection of the applicable check valve(s):
  • CHECK VALVE-FUEL DRAIN, L WING TK INR FWD [50QM] ( CHECK VALVE-FUEL DRAIN, R WING TK INR FWD [51QM] )
  • CHECK VALVE-FUEL DRAIN, L WING TK OUTR [52QM] ( CHECK VALVE-FUEL DRAIN, R WING TK OUTR [53QM] )
  • CHECK VALVE-FUEL DRAIN, L WING TK INR REAR [120QM] ( CHECK VALVE-FUEL DRAIN, R WING TK INR REAR [121QM] )
  • CHECK VALVE-FUEL DRAIN, CTR TK [93QM] .
     (c) If there is damage to the applicable valve, replace it:
     (d) Make sure that the access to the fuel tank is closed AMM 28-10-00-910-002.
     (e) Do the test in Para. 3. A.
   (10) If the fault continues:
     (a) Get access to the fuel tanks AMM 28-10-00-910-001 and AMM 28-10-00-910-002.
     (b) Do a visual inspection of the applicable vent float valve(s) VALVE-FLOAT VENT, L WING TK INR [16QM] ( VALVE-FLOAT VENT, R WING TK INR [17QM] ) or VALVE-FLOAT VENT, L WING TK OUTR [15QM] ( VALVE-FLOAT VENT, R WING TK OUTR [18QM] ).
     (c) Make sure that there is no damage and the valve moves freely through its full range of movement.
     (d) If there is damage or the valve does not move freely, replace it:
     (e) Make sure that the access to the fuel tank is closed AMM 28-10-00-910-002.
     (f) Do the test in Para. 3. A.
   (11) If the fault continues:
     (a) Get access to the fuel tanks AMM 28-10-00-910-001 and AMM 28-10-00-910-002.
     (b) Do an inspection of the vent pipes and structure AMM 28-11-00-280-003 in the applicable wing tank for:
  • Damage
  • Signs of possible fuel leakage into the surge tank.
       1 If there is damage, then repair or replace the applicable components in the vent system AMM 28-00-00-000-001 and AMM 28-00-00-400-001.
     (c) Make sure that the access to the fuel tank is closed AMM 28-10-00-910-002.
     (d) Do the test in Para. 3. A.
Subtask 28-46-00-810-061-B ** ON A/C NOT FOR ALL
A. Procedure
   (1) Do the steps applicable to the test equipment available.
   (2) Test Equipment.
WARNING: WHEN YOU DO WORK ON THE FUEL SYSTEM WIRING, YOU MUST USE TEST EQUIPMENT THAT IS APPROVED (REFER TO INTERNATIONAL OR NATIONAL SPECIFICATIONS FOR INTRINSICALLY SAFE TEST EQUIPMENT: EN50020, UL913 OR EQUIVALENT). TEST EQUIPMENT THAT IS NOT APPROVED CAN CAUSE FIRE OR AN EXPLOSION.
     (a) If there is:

  • approved test equipment available, go to Step (3)

  • no approved test equipment available, go to Step (6).
   (3) Get access to the tank wall connector 4047VC1(2)-A (for the vent surge tank harness 34QJ1(2)) AMM 28-46-43-000-001.
   (4) Disconnect the free connector 4047VC1(2)-A from the receptacle 4047VC1(2).
   (5) Do a resistance check of the sensor 28QJ1(2) at the tank wall connector 4047VC1(2) between pins A and B AWM 284611 and AWM 284612.
Make sure the resistance is between 330 and 480 ohms.
If there is:

  • continuity as specified above, go to Step (6)

  • no continuity as specified above (resistance check out of range), go to Step (8).
NOTE: The sensor status (wet or dry) and fuel/air temperature will have an effect on the resistance value.
   (6) Replace the FLSCU-1 [7QJ] ( FLSCU-2 [9QJ] ) AMM 28-46-34-000-001 and AMM 28-46-34-400-001.
   (7) If the fault continues:
     (a) Get access to the tank wall connector 4047VC1(2)-A (for the vent surge tank harness 34QJ1(2)) AMM 28-46-43-000-001.
     (b) Disconnect the free connector 4047VC1(2)-A from the receptacle 4047VC1(2).
     (c) Do a check AWM 284611, and AWM 284612 of the aircraft wiring (sensor input line - H) between the FLSCU-1(2) rack connector AB, pin 14A and the tank wall free connector 4047VC1(2)-A, pin A.
     (d) Do a check AWM 284611, and AWM 284612 of the aircraft wiring (sensor input line - L) between the FLSCU-1(2) rack connector AB, pin 14B and the tank wall free connector 4047VC1(2)-A, pin B.
     (e) Do a check AWM 284601 of the aircraft wiring (FLSCU-1 BITE 1 test command line) between the FLSCU-1 rack connector AA, pin 15B and the FQIC rack connector AB, pin 14F or the (aircraft wiring (FLSCU-2 BITE 1 test command line) between the FLSCU-2 rack connector AA, pin 15B and the FQIC rack connector AB, pin 12F).
     (f) Do a check AWM 284606 of the aircraft wiring (FLSCU-1 LS4 output line) between the FLSCU-1 rack connector AB, pin 1B and the FQIC rack connector AC, pin 4G or the (aircraft wiring (FLSCU-2 LS4 output line) between the FLSCU-2 rack connector AB, pin 1B and the FQIC rack connector AC, pin 1K).
     (g) Repair all the unserviceable wiring and connectors ESPM 2053210.
     (h) Connect the free connector 4047VC1(2)-A to the receptacle 4047VC1(2).
     (i) Do the test in Para. 3.A.
   (8) If the fault continues or if there is no continuity in Step (5):
     (a) Drain, open and vent the tank AMM 28-10-00-910-001 and AMM 28-10-00-910-002.
     (b) Do a wiring check of the HARNESS-L VENT SURGE TK [34QJ1] ( HARNESS-R VENT SURGE TK [34QJ2] ) AWM 284611 ( AWM 284612) and replace, if necessary AMM 28-46-43-000-001 and AMM 28-46-43-400-001.
     (c) If the harness is serviceable, replace the SENSOR-HIGH LVL, LEFT WING SURGE TK CHANNEL A [28QJ1] ( SENSOR-HIGH LVL, RIGHT WING SURGE TK CHANNEL A [28QJ2] ) AMM 28-46-16-000-001 and AMM 28-46-16-400-001.
   (9) If the fault continues:
     (a) Get access to the fuel tanks AMM 28-10-00-910-001 and AMM 28-10-00-910-002.
     (b) Do a visual inspection of the applicable check valve(s):
  • CHECK VALVE-FUEL DRAIN, L WING TK INR FWD [50QM] ( CHECK VALVE-FUEL DRAIN, R WING TK INR FWD [51QM] )
  • CHECK VALVE-FUEL DRAIN, L WING TK OUTR [52QM] ( CHECK VALVE-FUEL DRAIN, R WING TK OUTR [53QM] )
  • CHECK VALVE-FUEL DRAIN, L WING TK INR REAR [120QM] ( CHECK VALVE-FUEL DRAIN, R WING TK INR REAR [121QM] )
  • CHECK VALVE-FUEL DRAIN, CTR TK [93QM] .
     (c) If there is damage to the applicable valve, replace it:
     (d) Make sure that the access to the fuel tank is closed AMM 28-10-00-910-002.
     (e) Do the test in Para. 3. A.
   (10) If the fault continues:
     (a) Get access to the fuel tanks AMM 28-10-00-910-001 and AMM 28-10-00-910-002.
     (b) Do a visual inspection of the applicable vent float valve(s) VALVE-FLOAT VENT, L WING TK INR [16QM] ( VALVE-FLOAT VENT, R WING TK INR [17QM] ) or VALVE-FLOAT VENT, L WING TK OUTR [15QM] ( VALVE-FLOAT VENT, R WING TK OUTR [18QM] ).
     (c) Make sure that there is no damage and the valve moves freely through its full range of movement.
     (d) If there is damage or the valve does not move freely, replace it:
     (e) Make sure that the access to the fuel tank is closed AMM 28-10-00-910-002.
     (f) Do the test in Para. 3. A.
   (11) If the fault continues:
     (a) Get access to the fuel tanks AMM 28-10-00-910-001 and AMM 28-10-00-910-002.
     (b) Do an inspection of the vent pipes and structure AMM 28-11-00-280-003 in the applicable wing tank for:
  • Damage
  • Signs of possible fuel leakage into the surge tank.
       1 If there is damage, then repair or replace the applicable components in the vent system AMM 28-00-00-000-001 and AMM 28-00-00-400-001.
     (c) Make sure that the access to the fuel tank is closed AMM 28-10-00-910-002.
     (d) Do the test in Para. 3. A.
[Rev.8 from Aug 2018] 2026.04.04 04:29:15 UTC
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