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 ECU adjust the fuel pump operation speed.

WIRING DIAGRAM

A01EV9WE01

INSPECTION PROCEDURE

Note

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

PROCEDURE


  1. PERFORM ACTIVE TEST USING INTELLIGENT TESTER (CONTROL THE FUEL PUMP / SPEED)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the tester on.

    4. Enter the following menus: Powertrain / Engine / Active Test / Control the Fuel Pump / Speed.

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

      OK
      Operating sounds can be heard from fuel pump.
      Result
      Result Proceed to
      NG A
      OK B

    B

    PERFORM ACTIVE TEST USING INTELLIGENT TESTER (CONTROL THE FUEL PUMP DUTY) Click here

    A

  2. CHECK TERMINAL VOLTAGE (POWER SOURCE OF FUEL PUMP CONTROL ECU ASSEMBLY)


    1. A01EUCLE01
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Fuel Pump Control ECU)

      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 Switch Condition Specified Condition
      N30-1 (+B) - Body ground Engine switch on (IG) 11 to 14 V

    NG

    CHECK HARNESS AND CONNECTOR (FUEL PUMP CONTROL ECU ASSEMBLY - NO. 1 INTEGRATION RELAY) Click here

    OK

  3. 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
      N30-4 (E) - Body ground Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

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


    1. Disconnect the fuel pump control ECU assembly connector.

    2. Disconnect the fuel pump connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      N30-6 (FP) - N11-4 (B) Always Below 1 Ω
      N30-5 (FP-) - N11-5 (E) Always Below 1 Ω
      N30-6 (FP) or N11-4 (B) - Body ground Always 10 kΩ or higher
      N30-5 (FP-) or N11-5 (E) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. INSPECT FUEL PUMP


    1. Inspect the fuel pump Click here.

      Tech Tips

      Perform "Inspection After Repair" after replacing the fuel pump Click here.


    NG

    REPLACE FUEL PUMP Click here

    OK

  6. 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
      N30-2 (FPC) - A25-18 (FPC) Always Below 1 Ω
      N30-2 (FPC) or A25-18 (FPC) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  7. REPLACE FUEL PUMP CONTROL ECU ASSEMBLY


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


    NEXT

  8. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED


    1. Check the fuel pump operation.

      OK
      Malfunction has been repaired successfully.

    NG

    REPLACE ECM Click here

    OK

    END

  9. CHECK HARNESS AND CONNECTOR (FUEL PUMP CONTROL ECU ASSEMBLY - NO. 1 INTEGRATION RELAY)


    1. Disconnect the fuel pump control ECU assembly connector.

    2. Remove the No. 1 integration relay from the engine room relay block and junction block assembly.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      N30-1 (+B) - 1C-6 Always Below 1 Ω
      N30-1 (+B) or 1C-6 - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  10. INSPECT NO. 1 INTEGRATION RELAY (EFI MAIN RELAY)


    1. Inspect the No. 1 integration relay (EFI MAIN relay) Click here.


    NG

    REPLACE NO. 1 INTEGRATION RELAY (EFI MAIN RELAY) Click here

    OK

    GO TO ECM POWER SOURCE CIRCUIT Click here

  11. PERFORM ACTIVE TEST USING INTELLIGENT TESTER (CONTROL THE FUEL PUMP DUTY)


    1. A01EYC5E04
      Text in Illustration
      *a

      Component with harness connected

      (Fuel Pump)

      Remove the fuel pump Click here.

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

    3. Connect the fuel pump connector.

      CAUTION:

      Confirm that no fuel remains inside or on the outside of the fuel pump.

    4. Connect the intelligent tester to the DLC3.

    5. Turn the engine switch on (IG).

    6. Turn the tester on.

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

    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 Tester Operation Specified Condition
      4 (B) - 5 (E) Fuel pump control duty: 25% 3.4 to 4.1 V
      Fuel pump control duty: 80% 10.0 to 12.5 V

    9. Enter the following menus: Powertrain / Engine / Active Test / Control the Fuel Pump / Speed.

    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 Tester Operation Specified Condition
      4 (B) - 5 (E) ON (Fuel pump control duty: 90%) 10.2 to 14.0 V

      Tech Tips


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

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


    NG

    REPLACE FUEL PUMP CONTROL ECU ASSEMBLY Click here

    OK

  12. 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
      N30-2 (FPC) - A25-18 (FPC) Always Below 1 Ω
      N30-2 (FPC) or A25-18 (FPC) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  13. REPLACE FUEL PUMP


    1. Replace the fuel pump Click here.


    NEXT

    CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED Click here

  14. REPLACE FUEL PUMP CONTROL ECU ASSEMBLY


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


    NEXT

  15. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED


    1. Check the fuel pump operation.

      OK
      Malfunction has been repaired successfully.

    NG

    REPLACE ECM Click here

    OK

    END