SFI SYSTEM Fuel Injector Circuit

DESCRIPTION

The fuel injectors are located on the intake manifold. They inject fuel into the cylinders based on the signals from the ECM.

WIRING DIAGRAM

A01LZGPE03

CAUTION / NOTICE / HINT

Note

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

PROCEDURE


  1. CHECK TERMINAL VOLTAGE (POWER SOURCE OF FUEL INJECTOR ASSEMBLY)


    1. A01LZ6HC26
      *a

      Front view of wire harness connector

      (to Fuel Injector Assembly)

      Disconnect the fuel injector assembly connectors.

    2. Turn the ignition switch to ON.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      B9-1 - Body ground Ignition switch ON 11 to 14 V
      B10-1 - Body ground Ignition switch ON 11 to 14 V
      B11-1 - Body ground Ignition switch ON 11 to 14 V
      B12-1 - Body ground Ignition switch ON 11 to 14 V
      Result
      Proceed to
      OK
      NG

    NG

    CHECK HARNESS AND CONNECTOR (FUEL INJECTOR ASSEMBLY - INJ RELAY) Click here

    OK

  2. INSPECT FUEL INJECTOR ASSEMBLY (INJECTION AND VOLUME)


    1. Inspect the fuel injector assembly.

      Click here

      Tech Tips

      Perform "Inspection After Repair" after replacing the fuel injector assembly.

      Click here

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE FUEL INJECTOR ASSEMBLY Click here

    OK

  3. CHECK HARNESS AND CONNECTOR (FUEL INJECTOR ASSEMBLY - ECM)


    1. Disconnect the fuel injector assembly connectors.

    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
      B9-2 - B186-98 (#10) Always Below 1 Ω
      B10-2 - B186-95 (#20) Always Below 1 Ω
      B11-2 - B186-96 (#30) Always Below 1 Ω
      B12-2 - B186-97 (#40) Always Below 1 Ω
      B9-2 or B186-98 (#10) - Body ground Always 10 kΩ or higher
      B10-2 or B186-95 (#20) - Body ground Always 10 kΩ or higher
      B11-2 or B186-96 (#30) - Body ground Always 10 kΩ or higher
      B12-2 or B186-97 (#40) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    OK

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

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  4. CHECK HARNESS AND CONNECTOR (FUEL INJECTOR ASSEMBLY - INJ RELAY)


    1. Disconnect the fuel injector assembly connectors.

    2. Remove the INJ 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
      B9-1 - 3 (INJ relay) Always Below 1 Ω
      B10-1 - 3 (INJ relay) Always Below 1 Ω
      B11-1 - 3 (INJ relay) Always Below 1 Ω
      B12-1 - 3 (INJ relay) Always Below 1 Ω
      B9-1 or 3 (INJ relay) - Body ground Always 10 kΩ or higher
      B10-1 or 3 (INJ relay) - Body ground Always 10 kΩ or higher
      B11-1 or 3 (INJ relay) - Body ground Always 10 kΩ or higher
      B12-1 or 3 (INJ relay) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. CHECK TERMINAL VOLTAGE (POWER SOURCE OF INJ RELAY)


    1. A01M0FDC01
      *1 Engine Room Relay Block and Junction Block Assembly
      *2 INJ Relay

      Remove the INJ relay from the engine room relay block and junction block assembly.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      5 (INJ relay) - Body ground Always 11 to 14 V
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (INJ RELAY - BATTERY)

    OK

  6. INSPECT INJ RELAY


    1. Inspect the INJ relay.

      Click here

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE INJ RELAY

    OK

  7. CHECK HARNESS AND CONNECTOR (INJ RELAY - BODY GROUND)


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

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      1 (INJ relay) - Body ground Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  8. CHECK HARNESS AND CONNECTOR (INJ RELAY - EFI-MAIN RELAY)


    1. Remove the INJ relay and EFI-MAIN relay from the engine room relay block and junction block assembly.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      2 (INJ relay) - 3 (EFI-MAIN relay) Always Below 1 Ω
      2 (INJ relay) or 3 (EFI-MAIN relay) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    OK

    GO TO ECM POWER SOURCE CIRCUIT Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR