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

B001H01E04

CAUTION / NOTICE / HINT

Note

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

PROCEDURE


  1. CHECK FUEL INJECTOR ASSEMBLY (POWER SOURCE)


    1. B001F5DE03
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Fuel Injector Assembly)

      Disconnect the fuel injector assembly connectors.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      C50-1 - Body ground Ignition switch ON 11 to 14 V
      C2-1 - Body ground Ignition switch ON 11 to 14 V
      C51-1 - Body ground Ignition switch ON 11 to 14 V
      C4-1 - Body ground Ignition switch ON 11 to 14 V
      Result
      Result Proceed to
      OK A
      NG B

    B

    CHECK HARNESS AND CONNECTOR (INJ NO. 2 RELAY - FUEL INJECTOR ASSEMBLY) Click here

    A

  2. INSPECT FUEL INJECTOR ASSEMBLY


    1. Inspect the fuel injector assembly Click here.

      Tech Tips

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


    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
      C50-2 - C154-4 (#10) Always Below 1 Ω
      C2-2 - C154-3 (#20) Always Below 1 Ω
      C51-2 - C154-2 (#30) Always Below 1 Ω
      C4-2 - C154-1 (#40) Always Below 1 Ω
      C50-2 or C154-4 (#10) - Body ground Always 10 kΩ or higher
      C2-2 or C154-3 (#20) - Body ground Always 10 kΩ or higher
      C51-2 or C154-2 (#30) - Body ground Always 10 kΩ or higher
      C4-2 or C154-1 (#40) - Body ground Always 10 kΩ or higher

    OK

    REPLACE ECM Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (FUEL INJECTOR ASSEMBLY - ECM)

  4. CHECK HARNESS AND CONNECTOR (INJ NO. 2 RELAY - FUEL INJECTOR ASSEMBLY)


    1. Disconnect the fuel injector assembly connectors.

    2. Remove the INJ NO. 2 relay from the engine room relay block.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      C50-1 - INJ NO. 2 relay terminal 3 Always Below 1 Ω
      C2-1 - INJ NO. 2 relay terminal 3 Always Below 1 Ω
      C51-1 - INJ NO. 2 relay terminal 3 Always Below 1 Ω
      C4-1 - INJ NO. 2 relay terminal 3 Always Below 1 Ω
      C50-1 or INJ NO. 2 relay terminal 3 - Body ground Always 10 kΩ or higher
      C2-1 or INJ NO. 2 relay terminal 3 - Body ground Always 10 kΩ or higher
      C51-1 or INJ NO. 2 relay terminal 3 - Body ground Always 10 kΩ or higher
      C4-1 or INJ NO. 2 relay terminal 3 - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (INJ NO. 2 RELAY - FUEL INJECTOR ASSEMBLY)

    OK

  5. INSPECT INJ NO. 2 RELAY


    1. Inspect the INJ NO. 2 relay Click here.


    NG

    REPLACE INJ NO. 2 RELAY

    OK

  6. CHECK HARNESS AND CONNECTOR (INJ NO. 2 RELAY - BATTERY)


    1. Remove the INJ NO. 2 relay from the engine room relay block.

    2. Disconnect the cable from the negative (-) battery terminal.

    3. Disconnect the cable from the positive (+) battery terminal.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      INJ NO. 2 relay terminal 5 - Positive battery terminal Always Below 1 Ω
      INJ NO. 2 relay terminal 5 or Positive battery terminal - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (INJ NO. 2 RELAY - BATTERY)

    OK

  7. CHECK HARNESS AND CONNECTOR (INJ NO. 2 RELAY - BODYGROUND)


    1. Remove the INJ NO. 2 relay from the engine room relay block.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      INJ No. 2 relay terminal 1 - Body ground Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (INJ NO. 2 RELAY - BODY GROUND)

    OK

  8. CHECK HARNESS AND CONNECTOR (INTEGRATION RELAY (EFI RELAY) - INJ NO. 2 RELAY)


    1. Remove the INJ NO. 2 relay from the engine room relay block.

    2. Remove the integration relay (EFI relay) from the engine room relay block.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      1B-4 - INJ NO. 2 relay terminal 2 Always Below 1 Ω
      1B-4 or INJ NO. 2 relay terminal 2 - Body ground Always 10 kΩ or higher

    OK

    CHECK ECM POWER SOURCE CIRCUIT Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (INTEGRATION RELAY (EFI RELAY) - INJ NO. 2 RELAY)