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Fuel Gauge Sending Unit Test

Special Tools Required 

Fuel sender wrench 07AAA-S0XA100

NOTE: For the fuel gauge sending system circuit diagram, refer to CIRCUIT DIAGRAM .
  1. Check the No. 9 BACK UP LIGHT INSTRUMENT LIGHT (10 A) fuse in the driver's under-dash fuse/ relay box before testing.
  2. Turn the ignition switch OFF.
  3. Remove the driver's side second row seat (see SECOND ROW SEAT REMOVAL/INSTALLATION ).
  4. Cut the carpet, then remove the access panel from the floor (see FUEL TANK UNIT REMOVAL/INSTALLATION  ).
  5. Disconnect the fuel pump 5P connector (A).
    Fig 1: Disconnecting Fuel Pump 5P Connector
    G03639972Courtesy of AMERICAN HONDA MOTOR CO., INC.
  6. Measure voltage between fuel pump 5P connector terminals No. 1 and No. 2 with the ignition switch ON (II). There should be between 5 and 8 V.
    • If the voltage is as specified, go to step 7.
    • If the voltage is not as specified, check for:
      • - an open in the YEL/BLU or BLK wire.
      • - poor ground (G501).
    Fig 2: Measuring Voltage Between Fuel Pump 5P Connector Terminals 1 And 2 With Ignition Switch ON (II)
    G03639973Courtesy of AMERICAN HONDA MOTOR CO., INC.
  7. Turn the ignition switch OFF.
  8. Install a 2 Ω resistor between fuel pump 5P connector terminals No. 1 and No. 2.
    Fig 3: Installing A 2 Ω Resistor Between Fuel Pump 5P Connector Terminals 1 And 2
    G03639974Courtesy of AMERICAN HONDA MOTOR CO., INC.
  9. Turn the ignition switch ON (II).
  10. Check that the pointer of the fuel gauge indicates "F".
    • If the pointer of the fuel gauge does not indicate "F", replace the gauge.
    • If the gauge is OK, inspect the fuel gauge sending unit.
      NOTE: The pointer of the fuel gauge returns to the bottom on the gauge dial when the ignition switch is OFF, regardless of the fuel level.
  11. Turn the ignition switch OFF.
  12. Remove the driver's side second row seat (see SECOND ROW SEAT REMOVAL/INSTALLATION ).
  13. Cut the carpet (be careful not to cut the wire harness), then remove the access panel from the floor (see FUEL TANK UNIT REMOVAL/INSTALLATION  ).
  14. Disconnect the fuel pump 5P connector.
  15. Remove the fuel fill cap.
  16. Relieve the fuel pressure (see FUEL PRESSURE RELIEVING  ).
  17. Disconnect the quick-connect fittings from the fuel tank unit.
  18. Using the special tool, loosen the fuel tank unit locknut (A). Remove the fuel tank unit.
    Fig 4: Loosening Fuel Tank Unit Locknut Using Special Tool
    G03639975Courtesy of AMERICAN HONDA MOTOR CO., INC.
  19. Measure resistance between the No. 1 and No. 2 terminals with the float at E (EMPTY), L (LOW), 1/2 (HALF FULL), and F (FULL) positions. If you do not get the following readings, replace the fuel gauge sending unit.
    FUEL LEVEL RESISTANCE REFERENCE

    Float Position Resistance (Ω)
    2003-2004 models 2005-2006 models
    F 11-13 19-21
    1/2 51.1-51.7 185-195
    LOW 101-116 484-613
    E 130-132 770-790
    Fig 5: Measuring Resistance Between Terminals 1 And 2 With Float At E (EMPTY), L (LOW), 1/2 (HALF FULL), And F (FULL) Positions (2003-04 Models)
    G03639976Courtesy of AMERICAN HONDA MOTOR CO., INC.
    Fig 6: Measuring Resistance Between Terminals 1 And 2 With Float At E (EMPTY), L (LOW), 1/2 (HALF FULL), And F (FULL) Positions (2005-06 Models)
    G03639977Courtesy of AMERICAN HONDA MOTOR CO., INC.
  20. If the resistance is not as specified, replace the fuel gauge sending unit (see FUEL PUMP/FUEL GAUGE SENDING UNIT REPLACEMENT  ).
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