СИСТЕМА SFI Fuel Pump Control Circuit

DESCRIPTION

When the engine is cranked, the starter relay drive signal from the engine switch is input into the STA terminal of the ECM, and the NE signal generated by the crankshaft position sensor is also input into the NE+ terminal. The ECM interprets that the engine is being cranked, and turns transistor Tr1 in the ECM internal circuit on. The current flows to the C/OPN (Circuit Opening) relay by turning Tr1 on. Then, the fuel pump operates.

While the NE signal is input into the ECM and the engine is running, Tr1 remains on after being turned on by the ECM.

A005S6JE01

WIRING DIAGRAM

A005SKJE01

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) and turn the tester on.

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

    4. Check whether the fuel pump operating sound occurs when performing the Active Test on the tester.

      Result
      Result Proceed to
      Fuel pump operating sound does not occur A
      Fuel pump operating sound occurs B
    B

    READ VALUE USING INTELLIGENT TESTER (STARTER SIGNAL) Click here

    A

  2. INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY (C/OPN RELAY INPUT VOLTAGE)

    1. Disconnect the DB and DF instrument panel junction block connectors.

      A005SD8E01

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      DB-11 - Body ground Engine switch off Below 1 V
      DF-4 - Body ground
      DB-11 - Body ground Engine switch on (IG) 11 to 14 V
      DF-4 - Body ground
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Instrument Panel Junction Block)
      Result
      Result Proceed to
      Outside standard range A
      Within standard range B

    3. Reconnect the instrument panel junction block connectors.

    B

    INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY (C/OPN RELAY) Click here

    A

  3. CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK - INTEGRATION RELAY)

    1. Remove the integration relay from the engine room No. 1 relay block.

      A005SA8E01

    2. Disconnect the DB and DF instrument panel junction block connectors.

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

      Standard Resistance (Check for Open)
      Tester Connection Condition Specified Condition
      1A-4 - DF-4 Always Below 1 Ω
      1B-4 - DB-11
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      1A-4 or DF-4 - Body ground Always 10 kΩ or higher
      1B-4 or DB-11 - Body ground
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Integration Relay)
      *2 Engine Room No. 1 Relay Block
      *3

      Front view of wire harness connector

      (to Instrument Panel Junction Block)

    4. Reinstall the integration relay.

    5. Reconnect the instrument panel junction block connectors.

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    GO TO ECM POWER SOURCE CIRCUIT Click here

  4. INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY (C/OPN RELAY)

    1. Remove the instrument panel junction block.

      A005VZUE01

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      DB-11 - DA-8 Battery voltage not applied 10 kΩ or higher
      Battery voltage applied to terminals DF-4 and DB-10 Below 1 Ω
      Text in Illustration
      *1

      Component without harness connected

      (Instrument Panel Junction Block)

    3. Reinstall the instrument panel junction block.

    NG

    REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY

    OK

  5. CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK - ECM)

    1. Disconnect the A40 ECM connector.

      A005TDUE02

    2. Disconnect the DB instrument panel junction block connector.

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

      Standard Resistance (Check for Open)
      Tester Connection Condition Specified Condition
      DB-10 - A40-7 (FC) Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      DB-10 or A40-7 (FC) - Body ground Always 10 kΩ or higher
      Text in Illustration
      *1

      Front view of wire harness connector

      (to ECM)
      *2

      Front view of wire harness connector

      (to Instrument Panel Junction Block)

    4. Reconnect the instrument panel junction block connector.

    5. Reconnect the ECM connector.

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  6. CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK - FUEL PUMP - BODY GROUND)

    1. Check the harness and connectors between the instrument panel junction block and fuel pump.

      A005W0SE01

      1. Disconnect the DA instrument panel junction block connector.

      2. Disconnect the G24 fuel pump connector.

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

        Standard Resistance (Check for Open)
        Tester Connection Condition Specified Condition
        DA-8 - G24-4 Always Below 1 Ω
        Standard Resistance (Check for Short)
        Tester Connection Condition Specified Condition
        DA-8 or G24-4 - Body ground Always 10 kΩ or higher
        Text in Illustration
        *1

        Front view of wire harness connector

        (to Instrument Panel Junction Block)
        *2

        Front view of wire harness connector

        (to Fuel Pump)

      4. Reconnect the instrument panel junction block connector.

      5. Reconnect the fuel pump connector.

    2. Check the harness and connectors between the fuel pump and body ground.

      1. Disconnect the G24 fuel pump connector.

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

        Standard Resistance
        Tester Connection Condition Specified Condition
        G24-5 - Body ground Always Below 1 Ω

      3. Reconnect the fuel pump connector.

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  7. INSPECT FUEL PUMP

    1. Inspect the fuel pump Click here.

    NG

    REPLACE FUEL PUMP Click here

    OK

    REPLACE ECM Click here

  8. READ VALUE USING INTELLIGENT TESTER (STARTER SIGNAL)

    1. Connect the intelligent tester to the DLC3.

    2. Turn the engine switch on (IG) and turn the tester on.

    3. Enter the following menus: Powertrain / Engine and ECT / Data List / Starter Signal.

    4. Check the result when the engine switch is on (IG) and when the engine is started.

      OK
      Condition Starter Signal
      Engine switch on (IG) OFF
      Engine started ON
    NG

    REPAIR OR REPLACE STARTING SYSTEM Click here

    OK

  9. READ VALUE USING INTELLIGENT TESTER (ENGINE SPEED)

    1. Connect the intelligent tester to the DLC3.

    2. Turn the engine switch on (IG) and turn the tester on.

    3. Enter the following menus: Powertrain / Engine and ECT / Data List / Engine Speed.

    4. Read the values displayed on the tester while cranking.

      OK
      Values are displayed continuously.
    NG

    REPAIR OR REPLACE CRANKSHAFT POSITION SENSOR CIRCUIT Click here

    OK

    REPLACE ECM Click here