SFI SYSTEM Fuel Pump Control Circuit

DESCRIPTION

The fuel pump circuit consists of the ECM, fuel pump and fuel pump control ECU (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. Based on the signal sent from the ECM, the fuel pump control ECU adjusts the fuel pump operation speed among 3 settings.

WIRING DIAGRAM

A005KCIE02

CAUTION / NOTICE / HINT

This troubleshooting procedure is based on the premise that the engine is started. If the engine is not started, proceed to Problem Symptoms Table Click here.

Note

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

PROCEDURE


  1. PERFORM ACTIVE TEST USING INTELLIGENT TESTER (FUEL PUMP)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the ignition switch to ON and turn the tester on.

    3. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Fuel Pump / Speed.

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

      OK
      Operating sounds can be heard from fuel pump.

    OK

    PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE Click here

    NG

  2. INSPECT FUEL PUMP CONTROL ECU (POWER SOURCE VOLTAGE)

    A005I51E02
    Text in Illustration
    *a

    Front view of wire harness connector

    (to Fuel Pump control ECU Assembly)

    1. Disconnect the fuel pump control ECU assembly connector.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      A60-6 (+B) - Body ground ignition switch ON 11 to 14 V

    3. Reconnect the fuel pump control ECU assembly connector.


    NG

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

    OK

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


    1. Disconnect the fuel pump 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 (Check for Open)
      Tester Connection Condition Specified Condition
      K17-4 - A60-1 (FP) Always Below 1 Ω
      K17-5 - Body ground Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      K17-4 or A60-1 (FP) - Body ground Always 10 kΩ or higher

    4. Reconnect the fuel pump control ECU assembly connector.

    5. Reconnect the fuel pump connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. INSPECT FUEL PUMP


    1. Inspect the fuel pump Click here.


    NG

    REPLACE FUEL PUMP Click here

    OK

  5. CHECK HARNESS AND CONNECTOR (FUEL PUMP CONTROL ECU ASSEMBLY - ECM, BODY GROUND)


    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 (Check for Open)
      Tester Connection Condition Specified Condition
      A60-5 (FPC) - A58-21 (FPC) Always Below 1 Ω
      A60-3 (E) - Body ground Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      A60-5 (FPC) or A58-21 (FPC) - Body ground Always 10 kΩ or higher

    4. Reconnect the ECM connector.

    5. Reconnect the fuel pump control ECU assembly connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  6. REPLACE FUEL PUMP CONTROL ECU ASSEMBLY


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


    NEXT

  7. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED


    1. Confirm whether malfunction has been repaired.

      Result
      Result Proceed to
      Malfunction has been repaired. A
      Malfunction has not been repaired. B

    A

    END

    B

    REPLACE ECM Click here

  8. 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 main relay block.

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

      Standard Resistance (Check for Open)
      Tester Connection Condition Specified Condition
      A60-6 (+B) - 1E-4 Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      A60-6 (+B) or 1E-4 - Body ground Always 10 kΩ or higher

    4. Reinstall the No. 1 integration relay.

    5. Reconnect the fuel pump control ECU assembly connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

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


    1. Inspect the No. 1 integration relay Click here.


    OK

    REPAIR OR REPLACE HARNESS OR CONNECTOR (NO. 1 INTEGRATION RELAY - BATTERY)

    NG

    REPLACE NO. 1 INTEGRATION RELAY Click here