SFI SYSTEM Fuel Pump Control Circuit

DESCRIPTION


  1. w/o Smart Entry and Start System

    When the engine is cranked, the starter relay drive signal output from the ignition 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. When the ECM interprets that the engine is cranked, it turns transistor Tr1 in the ECM internal circuit on. The current flows to the C/OPN (Circuit Opening) relay when Tr1 is turned on. Then, the fuel pump operates.

    While the NE signal is input into the ECM when the engine is running, the ECM turns Tr1 on continuously.

  2. w/ Smart Entry and Start System

    When the engine is cranked, the starter relay drive signal output from the STAR terminal of the power management control ECU 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. When the ECM interprets that the engine is cranked, it turns transistor Tr1 in the ECM internal circuit on. The current flows to the C/OPN (Circuit Opening) relay when Tr1 is turned on. Then, the fuel pump operates.

    While the NE signal is input into the ECM when the engine is running, the ECM turns Tr1 on continuously.

    A01EJZ3E03
    A01EMCAE03

WIRING DIAGRAM

A01EIT8E03
A01EK2RE02

INSPECTION PROCEDURE

Note

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

PROCEDURE


  1. PERFORM ACTIVE TEST USING GTS (ACTIVE THE FUEL PUMP SPEED CONTROL)


    1. Connect the GTS to the DLC3.

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

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

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

      OK
      Fuel pump operating sound occurs.

    NG

    INSPECT ENGINE ROOM JUNCTION BLOCK ASSEMBLY (C/OPN RELAY) Click here

    OK

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

  2. INSPECT ENGINE ROOM JUNCTION BLOCK ASSEMBLY (C/OPN RELAY)


    1. Inspect the C/OPN relay Click here.


    NG

    REPLACE ENGINE ROOM JUNCTION BLOCK ASSEMBLY Click here

    OK

  3. CHECK HARNESS AND CONNECTOR (C/OPN RELAY - ECM)


    1. Disconnect the ECM connector.

    2. Remove the engine room junction block assembly from the engine room relay block.

    3. Disconnect the engine room junction block assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      1F-3 - A49-8 (FC) Always Below 1 Ω
      1F-3 or A49-8 (FC) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. INSPECT ENGINE ROOM RELAY BLOCK (IG2 RELAY - C/OPN RELAY)


    1. Remove the IG2 relay from the engine room relay block.

    2. Remove the engine room junction block assembly from the engine room relay block.

    3. Disconnect the engine room junction block assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      1F-2 - 5 (IG2 relay terminal) Always Below 1 Ω
      1F-2 or 5 (IG2 relay terminal) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (IG2 RELAY - C/OPN RELAY)

    OK

  5. CHECK HARNESS AND CONNECTOR (C/OPN RELAY - FUEL PUMP)


    1. Remove the engine room junction block assembly from the engine room relay block.

    2. Disconnect the engine room junction block assembly connector.

    3. Disconnect the fuel pump connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      1F-10 - L12-4 Always Below 1 Ω
      1F-10 or L12-4 - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  6. CHECK HARNESS AND CONNECTOR (FUEL PUMP - BODY GROUND)


    1. Disconnect the fuel pump connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      L12-5 - Body ground Always Below 1 Ω

    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