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Fuel Pump Circuit Troubleshooting

NOTE: Information marked with an asterisk (*) applies to '06-08 models.

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 left kick panel (see TRIM REMOVAL/INSTALLATION - DOOR AREAS ), 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)
    G05490767Courtesy of AMERICAN HONDA MOTOR CO., INC.
  3. Turn the ignition switch ON (II).
  4. 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 No. 4 And Body Ground
    G05490768Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  - Go to step 5.

    NO  -

    • Replace PGM-FI main relay 1 (Fl MAIN).
    • If needed, replace the under-dash fuse/relay box.
  5. Measure voltage between PGM-FI main relay 2 (FUEL PUMP) 4P connector terminal No. 1 and body ground.
    Fig 3: Measuring Voltage Between PGM-FI Main Relay 2 (FUEL PUMP) 4P Connector Terminal No. 1 And Body Ground
    G05490769Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  - Go to step 6.

    NO  -

    • Replace the No. 19 FUEL PUMP (15 A) fuse in the under-dash fuse/relay box.
    • If needed, replace the under-dash fuse/relay box.

  6. Turn the ignition switch OFF.
  7. Connect PGM-FI main relay 2 (FUEL PUMP) 4P connector terminal No. 3 to body ground with a jumper wire.
    Fig 4: Connecting PGM-FI Main Relay 2 (FUEL PUMP) 4P Connector Terminal No. 3 To Body Ground With Jumper Wire
    G05490770Courtesy of AMERICAN HONDA MOTOR CO., INC.
  8. Turn the ignition switch OFF.
  9. Jump the SCS line with the HDS.
  10. Disconnect ECM/PCM connector E (31P).
  11. Check for continuity between body ground and ECM/PCM connector terminal E17.
    Fig 5: Checking Continuity Between Body Ground And ECM/PCM Connector Terminal E17
    G05490771Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Go to step 12.

    NO  - Repair open in the wire between PGM-FI main relay 2 (FUEL PUMP) and the ECM/PCM (E17).

  12. Reinstall PGM-FI main relay 2 (FUEL PUMP).
  13. Connect ECM/PCM connector terminal E7 to body ground with a jumper wire.
    Fig 6: Connecting ECM/PCM Connector Terminal E7 To Body Ground With Jumper Wire
    G05490772Courtesy of AMERICAN HONDA MOTOR CO., INC.
  14. Turn the ignition switch ON (II).
  15. Measure voltage between ECM/PCM connector terminal E17 and body ground.
    Fig 7: Measuring Voltage Between ECM/PCM Connector Terminal E17 And Body Ground
    G05490773Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  - Go to step 16.

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

  16. Turn the ignition switch OFF.
  17. Reconnect ECM/PCM connector E (31P), and disconnect the jumper wire.
  18. Open the SCS line with the HDS.
  19. Turn the ignition switch OFF.
  20. Turn the ignition switch ON (II), and measure voltage between ECM/PCM connector terminal E17 and body ground within 2 seconds.
    Fig 8: Measuring Voltage Between ECM/PCM Connector Terminal E17 And Body Ground
    G05490774Courtesy 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; '04-05 models (see '04-05 MODELS ), '06-08 models (see '06-08 MODELS ).

    NO  - Go to step 21.

  21. Turn the ignition switch OFF.
  22. Remove the trunk floor.
  23. Remove the access panel from the floor.
  24. Turn the ignition switch ON (II), and measure voltage between fuel tank unit 5P connector terminal No. 5 and body ground within the first 2 seconds.
    Fig 9: Measuring Voltage Between Fuel Tank Unit 5P Connector Terminal No. 5 And Body Ground
    G05490775Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  - Go to step  29.

    NO  - Go to step 25.

  25. Turn the ignition switch OFF.
  26. Remove PGM-FI main relay 2 (FUEL PUMP).
  27. Connect PGM-FI main relay 2 (FUEL PUMP) 4P connector terminals No. 1 and No. 2 with a jumper wire.
    Fig 10: Connecting PGM-FI Main Relay 2 (FUEL PUMP) 4P Connector Terminals No. 1 And No. 2 With Jumper Wire
    G05490776Courtesy of AMERICAN HONDA MOTOR CO., INC.
  28. Turn the ignition switch ON (II), and measure voltage between fuel tank unit 5P connector terminal No. 5 and body ground.
    Fig 11: Measuring Voltage Between Fuel Tank Unit 5P Connector Terminal No. 5 And Body Ground
    G05490777Courtesy 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 5P connector.

  29. Turn the ignition switch OFF.
  30. Check for continuity between fuel tank unit 5P connector terminal No. 4 and body ground.
    Fig 12: Checking Continuity Between Fuel Tank Unit 5P Connector Terminal No. 4 And Body Ground
    G05490778Courtesy 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 5P connector and G603.

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