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Fuel Gauge Sending Unit Test

NOTE: For the fuel gauge system circuit diagram, refer to the Gauges Circuit Diagram (see CIRCUIT DIAGRAM - GAUGE CONTROL MODULE (TACH) ).
  1. Check the No. 10 METER (7.5 A) fuse in the under- dash fuse/relay box before testing.
  2. Check for body electrical system DTCs.
  3. Turn the ignition switch OFF.
  4. Remove the rear seat cushion (see SEAT CUSHION ).
  5. Remove the rear floor upper cross-member (A).
    Fig 1: Identifying Rear Floor Upper Cross-Member
    G06264753Courtesy of AMERICAN HONDA MOTOR CO., INC.
  6. Remove the access panel (A) from the floor.
    Fig 2: Identifying Fuel Tank Unit 4P Connector And Access Panel
    G06264754Courtesy of AMERICAN HONDA MOTOR CO., INC.
  7. Disconnect the fuel tank unit 4P connector (B).
  8. Measure voltage between fuel tank unit 4P connector terminals No. 1 and No. 3 with the ignition switch ON (II). There should be battery voltage.
    • If the voltage is OK, go to step 9.
    • If the voltage is not as specified, check for:
      • a short in the ORN wire to ground.
      • an open in the ORN or LT GRN wire.
        Fig 3: Identifying Fuel Tank Unit 4P Connector Terminal
        G06264755Courtesy of AMERICAN HONDA MOTOR CO., INC.
  9. Turn the ignition switch OFF.
  10. Remove the fuel tank unit from the fuel tank (see FUEL TANK UNIT REMOVAL/INSTALLATION  ).
  11. Measure resistance between fuel tank unit 4P connector terminals No. 1 and No. 3 with the float at E (EMPTY), LOW (LOW FUEL INDICATOR), 1/2 (HALF FULL), and F (FULL) positions. If you do not get the following readings, replace the fuel gauge sending unit (see FUEL PUMP/FUEL GAUGE SENDING UNIT REPLACEMENT  ).
    FLOAT POSITION

    Float Position F 139.8 mm (5.6 in.) 1/2 72.1 mm (2.9 in.) LOW 19.5 mm (0.8 in.) E 8.9 mm (0.4 in.)
    Resistance (Ω) 19 to 21 205.8 to 215.8 537.5 to 707 772 to 788
    Fig 4: Measuring Resistance Between Fuel Tank Unit 4P Connector Terminals No. 1 And No. 3
    G06264756Courtesy of AMERICAN HONDA MOTOR CO., INC.
  12. Reconnect the fuel tank unit 4P connector.
  13. Remove the No. 23 BACK UP (10 A) fuse from the under-hood fuse/relay box for at least 10 seconds, then reinstall it.
  14. Turn the ignition switch ON (II).
  15. Check that the pointer of the fuel gauge indicates "F" with the float at F.
    • If the pointer of the fuel gauge does not indicate "F", replace the gauge assembly.
    • If the gauge is OK, the test is complete.
      NOTE:
      • The pointer of the fuel gauge returns to the bottom of the gauge dial when the ignition switch is OFF, regardless of the fuel level.
      • Remove the No. 23 BACK UP (10 A) fuse from the under-hood fuse/relay box for at least 10 seconds after completing troubleshooting, otherwise it may take up to 20 minutes for the fuel gauge to indicate the correct fuel level.
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