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 to ON (II). If the fuel pump does not make noise, check as follows:
- Turn the ignition switch to LOCK (0).
- 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.
- Reinstall the under-dash fuse/relay box.
- Turn the ignition switch to ON (II).
- Measure the 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
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there battery voltage?
YES -Go to step 13.
NO -Go to step 6.
- Turn the ignition switch to LOCK (0).
- Disconnect under-hood fuse/relay box connector D (8P).
- Jump the SCS line with the HDS.
- Disconnect PCM connector A (44P).
- Disconnect under-dash fuse/relay box connector G (21P).
- Connect under-dash fuse/relay box connector G (21P) terminal No. 4 to body ground with a jumper wire.
- Check for continuity between under-hood fuse/relay box connector D (8P) terminal No. 6 and body ground.Fig 4: Checking Continuity Between Under-Hood Fuse/Relay Box Connector D (8P) Terminal No. 6 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there continuity?
YES -
- Replace PGM-FI main relay 1.
- If needed, replace the under-hood fuse/relay box (see REMOVAL AND INSTALLATION ).
NO -Repair an open in the wire between the under-hood fuse/relay box and the under-dash fuse/relay box.
- Measure the 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 No. 1 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there battery voltage?
YES -Go to step 14.
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 ).
- Turn the ignition switch to LOCK (0).
- Connect PGM-FI main relay 2 (FUEL PUMP) 4P connector terminal No. 3 to body ground with a jumper wire.
- Jump the SCS line with the HDS.
- Disconnect PCM connector A (44P).
- Check for continuity between body ground and PCM connector terminal A15.
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there continuity?
YES -Go to step 19.
NO -Repair an open in the wire between PGM-FI main relay 2 (FUEL PUMP) and the PCM (A15).
- Remove the under-dash fuse/relay box (see REMOVAL AND INSTALLATION ), then reinstall PGM-FI main relay 2 (FUEL PUMP).
- Reinstall the under-dash fuse/relay box (see REMOVAL AND INSTALLATION ).
- Connect PCM connector terminal A6 to body ground with a jumper wire.
- Turn the ignition switch to ON (II).
- Measure the voltage between PCM connector terminal A15 and body ground.
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there battery voltage?
YES -Go to step 24.
NO -Replace PGM-FI main relay 2 (FUEL PUMP).
- Turn the ignition switch to LOCK (0).
- Reconnect PCM connector A (44P).
- Within 2 seconds after turning the ignition switch to ON (II), measure the voltage between under-dash fuse/relay box connector F (34P) terminal No. 10 and body ground.Fig 10: Measuring Voltage Between Under-Dash Fuse/Relay Box Connector F (34P) Terminal No. 10 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there battery voltage?
YES -Update the PCM if it does not have the latest software (see PCM UPDATE ), or substitute a known-good PCM (see SUBSTITUTING THE PCM ), then recheck. If the symptom/indication goes away with a known-good PCM, replace the original PCM (see PCM REPLACEMENT ).
NO -Go to step 27.
- Within 2 seconds after turning the ignition switch to ON (II), measure the voltage between under-dash fuse/relay box connector F (34P) terminal No. 10 and body ground.Fig 11: Measuring Voltage Between Under-Dash Fuse/Relay Box Connector F (34P) Terminal No. 10 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there battery voltage?
YES -Go to step 28.
NO -If needed, replace the under-dash fuse/relay box (see REMOVAL AND INSTALLATION ), then go to step 28.
- Turn the ignition switch to LOCK (0).
- Fold the driver's side rear seat forward, and pull back the carpet to expose the access panel.
- Remove the access panel from the floor.
- Turn the ignition switch to ON (II), and measure the voltage between fuel tank unit 4P connector terminal No. 2 and body ground within 2 seconds.
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there battery voltage?
YES -Go to step 36.
NO -Go to step 32.
- Turn the ignition switch to LOCK (0).
- Remove PGM-FI main relay 2 (FUEL PUMP).
- Connect PGM-FI main relay 2 (FUEL PUMP) 4P connector terminals No. 1 and No. 2 with a jumper wire.
- Turn the ignition switch to ON (II), and measure the voltage between fuel tank unit 4P connector terminal No. 2 and body ground within 2 seconds.
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there battery voltage?
YES -Replace PGM-FI main relay 2 (FUEL PUMP).
NO -Repair an open in the wire between PGM-FI main relay 2 (FUEL PUMP) and the fuel tank unit 4P connector.
- Turn the ignition switch to LOCK (0).
- Check for continuity between fuel tank unit 4P connector terminal No. 4 and body ground.
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there continuity?
YES -Replace the fuel pump (see FUEL PUMP/FUEL GAUGE SENDING UNIT REPLACEMENT ).
NO -Repair an open in the wire between the fuel tank unit 4P connector and G602 (see STARTER SUBHARNESS ('07-09 MODELS) ).