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Fuel Pump Circuit Troubleshooting

If you suspect a problem with the fuel pump, check that the fuel pump actually runs; when it is on, you will hear some noise if you listen to the fuel fill port with the fuel fill cap removed. The fuel pump should run for 2 seconds when the ignition switch is first turned on. If the fuel pump does not make noise, check as follows:

  1. Turn the ignition switch OFF.
  2. Remove the under-dash fuse/relay box (see REMOVAL AND INSTALLATION ), then remove PGM-FI main relay 2 (FUEL PUMP) (A) from the under-dash fuse/relay box.
    Fig 1: Identifying PGM-FI Main Relay 2 (Fuel Pump)
    G06264701Courtesy of AMERICAN HONDA MOTOR CO., INC.
  3. Reinstall the under-dash fuse/relay box.
  4. Turn the ignition switch ON (II).
  5. Measure voltage between PGM-FI main relay 2 (FUEL PUMP) 4P connector terminal No. 4 and body ground.
    Fig 2: Measuring Voltage Between PGM-FI Main Relay 2 (Fuel Pump) 4P Connector Terminal 4 And Body Ground
    G06264702Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Go to step  12.

    NO  -Go to step 6.

  6. Turn the ignition switch OFF.
  7. Disconnect the under-hood fuse/relay box connector E(1 OP).
  8. Disconnect C101 connector at left side of engine compartment (see ENGINE COMPARTMENT WIRE HARNESS (LEFT BRANCH) ).
  9. Disconnect the under-dash fuse/relay box connector G (21P).
  10. Connect under-dash fuse/relay box connector G (21P) terminal No. 4 to body ground with a jumper wire.
    Fig 3: Connecting Under-Dash Fuse/Relay Box Connector G (21P) Terminal 4 To Body Ground With Jumper Wire
    G06264703Courtesy of AMERICAN HONDA MOTOR CO., INC.
  11. Check for continuity between under-hood fuse/ relay box connector E (1 OP) terminal No. 5 and body ground.
    Fig 4: Checking Continuity Between Under-Hood Fuse/ Relay Box Connector E (1Op) Terminal 5 And Body Ground
    G06264704Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -

    NO  -Repair open in the wire between the under- hood fuse/relay box and the under-dash fuse/relay box.

  12. Measure voltage between PGM-FI main relay 2 (FUEL PUMP) 4P connector terminal No. 1 and body ground.
    Fig 5: Measuring Voltage Between PGM-FI Main Relay 2 (Fuel Pump) 4P Connector Terminal 1 And Body Ground
    G06264705Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Go to step 13.

    NO  -

    • Check the No. 2 FUEL PUMP (15 A) fuse in the under-dash fuse/relay box.
    • If needed, replace the under-dash fuse/relay box (see REMOVAL AND INSTALLATION ).
  13. Turn the ignition switch OFF.
  14. Connect PGM-FI main relay 2 (FUEL PUMP) 4P connector terminal No. 3 to body ground with a jumper wire.
    Fig 6: Connecting PGM-FI Main Relay 2 (Fuel Pump) 4P Connector Terminal 3 To Body Ground With Jumper Wire
    G06264706Courtesy of AMERICAN HONDA MOTOR CO., INC.
  15. Jump the SCS line with the HDS.
  16. Disconnect ECM/PCM connector A (44P).
  17. Check for continuity between body ground and ECM/PCM connector terminal A15.
    Fig 7: Checking Continuity Between ECM/PCM Connector Terminal A15 Body Ground
    G06264707Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 18.

    NO  -Repair open in the wire between PGM-FI main relay 2 (FUEL PUMP) and the ECM/PCM (A15).

  18. Remove the under-dash fuse/relay box (see REMOVAL AND INSTALLATION ), then reinstall PGM-FI main relay 2 (FUEL PUMP).
  19. Reinstall the under-dash fuse/relay box (see REMOVAL AND INSTALLATION ).
  20. Connect ECM/PCM connector terminal A6 to body ground with a jumper wire.
    Fig 8: Connecting ECM/PCM Connector Terminal A6 To Body Ground With Jumper Wire
    G06264708Courtesy of AMERICAN HONDA MOTOR CO., INC.
  21. Turn the ignition switch ON (II).
  22. Measure voltage between ECM/PCM connector terminal A15 and body ground.
    Fig 9: Measuring Voltage Between ECM/PCM Connector Terminal A15 And Body Ground
    G06264709Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Go to step 23.

    NO  -Replace PGM-FI main relay 2 (FUEL PUMP).

  23. Turn the ignition switch OFF.
  24. Reconnect ECM/PCM connector A (44P).
  25. Open the SCS line with the HDS.
  26. Turn the ignition switch OFF.
  27. Turn the ignition switch ON (II), and measure voltage between under-dash fuse/relay box connector F (34P) terminal No. 10 and body ground within 2 seconds.
    Fig 10: Measuring Voltage Between Under-Dash Fuse/Relay Box Connector F (34P) Terminal 10 And Body Ground
    G06264710Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Update the ECM/PCM if it does not have the latest software (see UPDATING THE ECM/PCM ), or substitute a known-good ECM/PCM (see SUBSTITUTING THE ECM/PCM ), then recheck. If the symptom/indication goes away with a known-good ECM/PCM, replace the original ECM/ PCM (see ECM/PCM REPLACEMENT ).

    NO  -Go to step 28.

  28. Turn the ignition switch ON (II), and measure voltage between under-dash fuse/relay box connector F (34P) terminal No. 10 and body ground after 2 seconds.
    Fig 11: Measuring Voltage Between Under-Dash Fuse/Relay Box Connector F (34P) Terminal 10 And Body Ground
    G06264711Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Go to step 29.

    NO  -If needed, replace the under-dash fuse/relay box (see REMOVAL AND INSTALLATION ), then go to step 29.

  29. Turn the ignition switch OFF.
  30. Remove the rear seat cushion (see SEAT CUSHION ).
  31. Remove the rear floor upper cross-member, then remove the access panel from the floor (see FUEL TANK UNIT REMOVAL/INSTALLATION  ).
  32. Turn the ignition switch ON (II), and measure voltage between fuel tank unit 4P connector terminal No. 2 and body ground within 2 seconds.
    Fig 12: Measuring Voltage Between Fuel Tank Unit 4P Connector Terminal 2 And Body Ground
    G06264712Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Go to step  37.

    NO  -Go to step 33.

  33. Turn the ignition switch OFF.
  34. Remove PGM-FI main relay 2 (FUEL PUMP).
  35. Connect PGM-FI main relay 2 (FUEL PUMP) 4P connector terminals No. 1 and No. 2 with a jumper wire.
    Fig 13: Connecting PGM-FI Main Relay 2 (Fuel Pump) 4P Connector Terminals 1 And 2 With Jumper Wire
    G06264713Courtesy of AMERICAN HONDA MOTOR CO., INC.
  36. Turn the ignition switch ON (II), and measure voltage between fuel tank unit 4P connector terminal No. 2 and body ground within 2 seconds.
    Fig 14: Measuring Voltage Between Fuel Tank Unit 4P Connector Terminal 2 And Body Ground
    G06264714Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Replace PGM-FI main relay 2 (FUEL PUMP).

    NO  -Repair open in the wire between PGM-FI main relay 2 (FUEL PUMP) and the fuel tank unit 4P connector.

  37. Turn the ignition switch OFF.
  38. Check for continuity between fuel tank unit 4P connector terminal No. 4 and body ground.
    Fig 15: Checking Continuity Between Fuel Tank Unit 4P Connector Terminal 4 And Body Ground
    G06264715Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Replace the fuel pump (see FUEL PUMP/FUEL GAUGE SENDING UNIT REPLACEMENT  ).

    NO  -Repair open in the wire between the fuel tank unit 4P connector and G601 (see FLOOR WIRE HARNESS (LEFT BRANCH) ).

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