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

A01HGA9E03

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. A01HHWUC01
      *a

      Front view of wire harness connector

      (to Fuel Injector Assembly)

      Disconnect the fuel injector assembly connectors.

    2. Turn the engine switch on (IG).

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      C36-1 - Body ground Engine switch on (IG) 11 to 14 V
      C35-1 - Body ground Engine switch on (IG) 11 to 14 V
      C52-1 - Body ground Engine switch on (IG) 11 to 14 V
      C51-1 - Body ground Engine switch on (IG) 11 to 14 V
      Result
      Proceed to
      OK
      NG

    NG

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

    OK

  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

      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
      C36-2 - C65-98 (#10) Always Below 1 Ω
      C35-2 - C65-95 (#20) Always Below 1 Ω
      C52-2 - C65-96 (#30) Always Below 1 Ω
      C51-2 - C65-97 (#40) Always Below 1 Ω
      C36-2 or C65-98 (#10) - Body ground and other terminals Always 10 kΩ or higher
      C35-2 or C65-95 (#20) - Body ground and other terminals Always 10 kΩ or higher
      C52-2 or C65-96 (#30) - Body ground and other terminals Always 10 kΩ or higher
      C51-2 or C65-97 (#40) - Body ground and other terminals 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 - EFI-MAIN NO.2 RELAY)


    1. Disconnect the fuel injector assembly connectors.

    2. Remove the EFI-MAIN NO. 2 relay from the No. 1 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
      C36-1 - 3 (EFI-MAIN NO. 2 relay holder) Always Below 1 Ω
      C35-1 - 3 (EFI-MAIN NO. 2 relay holder) Always Below 1 Ω
      C52-1 - 3 (EFI-MAIN NO. 2 relay holder) Always Below 1 Ω
      C51-1 - 3 (EFI-MAIN NO. 2 relay holder) Always Below 1 Ω
      C36-1 or 3 (EFI-MAIN NO. 2 relay holder) - Body ground and other terminals Always 10 kΩ or higher
      C35-1 or 3 (EFI-MAIN NO. 2 relay holder) - Body ground and other terminals Always 10 kΩ or higher
      C52-1 or 3 (EFI-MAIN NO. 2 relay holder) - Body ground and other terminals Always 10 kΩ or higher
      C51-1 or 3 (EFI-MAIN NO. 2 relay holder) - Body ground and other terminals Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. INSPECT EFI-MAIN NO. 2 RELAY


    1. Inspect the EFI-MAIN NO. 2 relay.

      Click here

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE EFI-MAIN NO. 2 RELAY

    OK

  6. CHECK HARNESS AND CONNECTOR


    1. Remove the EFI-MAIN NO. 1 relay and EFI-MAIN NO. 2 relay from the No. 1 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
      3 (EFI-MAIN NO. 1 relay holder) - 2 (EFI-MAIN NO. 2 relay holder) Always Below 1 Ω
      1 (EFI-MAIN NO. 2 relay holder) - Body ground and other terminals Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  7. CHECK TERMINAL VOLTAGE (EFI-MAIN NO. 2 RELAY)


    1. Remove the EFI-MAIN NO. 2 relay from the No. 1 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 (EFI-MAIN NO. 2 relay holder) - Body ground Always 11 to 14 V
      Result
      Proceed to
      OK
      NG

    OK

    CHECK ECM POWER SOURCE CIRCUIT Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (NO. 1 ENGINE ROOM RELAY BLOCK AND JUNCTION BLOCK ASSEMBLY - BATTERY)