SFI SYSTEM Fuel Pump Control Circuit

DESCRIPTION

The fuel pump circuit consists of the ECM, fuel pump and fuel pump control ECU assembly (which operates the fuel pump). Based on the engine output, the ECM determines the fuel pump speed. The speed is then converted to a duty signal and sent to the fuel pump control ECU assembly. Based on the signal sent from the ECM, the fuel pump control ECU adjust the fuel pump operation speed.

WIRING DIAGRAM

A01W47CE09

CAUTION / NOTICE / HINT

Note

Inspect the fuses for circuits related to this system before performing the following inspection procedure.

PROCEDURE


  1. PERFORM ACTIVE TEST USING GTS (ACTIVATE THE CIRCUIT RELAY)


    1. Connect the GTS to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the GTS on.

    4. Enter the following menus: Powertrain / Engine / Active Test / Activate the Circuit Relay.

    5. Check whether operating sounds can be heard while operating the fuel pump using the GTS.

      OK
      Operating sounds can be heard from the fuel pump.

    NG

    INSPECT FUEL PUMP CONTROL ECU ASSEMBLY (POWER SOURCE VOLTAGE) Click here

    OK

  2. PERFORM ACTIVE TEST USING GTS (CONTROL THE FUEL PUMP DUTY RATIO, ACTIVATE THE CIRCUIT RELAY)


    1. A01W26KE01
      Text in Illustration
      *a

      Component with harness connected

      (Fuel Pump [for Low Pressure Side])

      Remove the fuel pump (for low pressure side) from the fuel tank assembly Click here.

    2. Clean the fuel pump to completely remove any remaining fuel.

    3. Connect the fuel pump connector.

      CAUTION:

      Make sure that there is no fuel remaining inside or on the outside of the fuel pump.

    4. Connect the GTS to the DLC3.

    5. Turn the engine switch on (IG).

    6. Turn the GTS on.

    7. Enter the following menus: Powertrain / Engine / Active Test / Control the Fuel Pump Duty Ratio.

    8. Operate the fuel pump using the Active Test function and measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection GTS Operation Specified Condition
      1 - 2 Fuel pump duty ratio: 25% 3.2 to 4.05 V
      Fuel pump duty ratio: 80% 8.8 to 12.5 V

    9. Enter the following menus: Powertrain / Engine / Active Test / Activate the Circuit Relay.

    10. Operate the fuel pump using the Active Test function and measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection GTS Operation Specified Condition
      1 - 2 ON (Fuel pump duty ratio: 90%) 9.0 to 14.0 V

      Tech Tips


      • Be sure to measure the voltage with all the connectors connected.

      • Before performing this inspection, check that the battery voltage is between 11 and 14 V (not depleted).


    NG

    INSPECT FUEL PUMP (FOR LOW PRESSURE SIDE) Click here

    OK

  3. INSPECT FUEL PUMP (FOR LOW PRESSURE SIDE)


    1. Inspect the fuel pump (for low pressure side) Click here.


    OK

    END

    NG

  4. REPLACE FUEL PUMP (FOR LOW PRESSURE SIDE)


    1. Replace the fuel pump (for low pressure side) Click here.

      Tech Tips

      Perform "Inspection After Repair" after replacing the fuel pump (for low pressure side) Click here.


    NEXT

  5. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED


    1. Check the fuel pump operation Click here.

      OK
      Malfunction has been repaired successfully.

    OK

    END

    NG

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Click here

  6. INSPECT FUEL PUMP CONTROL ECU ASSEMBLY (POWER SOURCE VOLTAGE)


    1. A01W0V9E01
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Fuel Pump Control ECU Assembly)

      Disconnect the fuel pump control ECU assembly connector.

    2. Turn the engine switch on (IG).

    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition
      P19-1 (+B) - P19-4 (E) Engine switch on (IG) 11 to 14 V

    NG

    CHECK HARNESS AND CONNECTOR (FUEL PUMP CONTROL ECU ASSEMBLY - BODY GROUND) Click here

    OK

  7. INSPECT FUEL PUMP (FOR LOW PRESSURE SIDE)


    1. Inspect the fuel pump (for low pressure side) Click here.

      Tech Tips

      Perform "Inspection After Repair" after replacing the fuel pump (for low pressure side) Click here.


    NG

    REPLACE FUEL PUMP (FOR LOW PRESSURE SIDE) Click here

    OK

  8. CHECK HARNESS AND CONNECTOR (FUEL PUMP (FOR LOW PRESSURE SIDE) - FUEL PUMP CONTROL ECU ASSEMBLY)


    1. Disconnect the fuel pump (for low pressure side) connector.

    2. Disconnect the fuel pump control ECU assembly connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      P7-4 (B) - P19-6 (FP) Always Below 1 Ω
      P7-5 (E) - P19-5 (FP-) Always Below 1 Ω
      P7-4 (B) or P19-6 (FP) - Body ground and other terminals Always 10 kΩ or higher
      P7-5 (E) or P19-5 (FP-) - Body ground and other terminals Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  9. CHECK HARNESS AND CONNECTOR (FUEL PUMP CONTROL ECU ASSEMBLY - ECM)


    1. Disconnect the fuel pump control ECU assembly connector.

    2. Disconnect the ECM connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      P19-2 (FPC) - A75-21 (FPC) Always Below 1 Ω
      P19-2 (FPC) or A75-21 (FPC) - Body ground and other terminals Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  10. REPLACE FUEL PUMP CONTROL ECU ASSEMBLY


    1. Replace the fuel pump control ECU assembly Click here.


    NEXT

  11. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED


    1. Check the fuel pump operation Click here.

      OK
      Malfunction has been repaired successfully.

    OK

    END

    NG

    REPLACE ECM Click here

  12. CHECK HARNESS AND CONNECTOR (FUEL PUMP CONTROL ECU ASSEMBLY - BODY GROUND)


    1. Disconnect the fuel pump control ECU assembly connector.

    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      P19-4 (E) - Body ground Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  13. CHECK HARNESS AND CONNECTOR (EFI MAIN2 RELAY - FUEL PUMP CONTROL ECU ASSEMBLY)


    1. Disconnect the No. 1 integration relay connector.

    2. Disconnect the fuel pump control ECU assembly connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      1C-6 - P19-1 (+B) Always Below 1 Ω
      1C-6 or P19-1 (+B) - Body ground and other terminals Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  14. INSPECT NO. 1 INTEGRATION RELAY (EFI MAIN2 RELAY)


    1. Inspect the EFI MAIN2 relay Click here.


    OK

    GO TO ECM POWER SOURCE CIRCUIT Click here

    NG

    REPLACE NO. 1 INTEGRATION RELAY Click here