SFI SYSTEM Starter Signal Circuit

DESCRIPTION

While the engine is being cranked, current flows from terminal ST1 of the ignition switch directly to terminal STA of the ECM (STA signal).

WIRING DIAGRAM

Refer to DTC P0617.

Click here

CAUTION / NOTICE / HINT

Note

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

PROCEDURE


  1. READ VALUE USING GTS (STARTER SIGNAL)


    1. Connect the GTS to DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

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


      Powertrain > Engine > Data List
      Tester Display
      Starter Signal

    5. Check the value displayed on the GTS when the ignition switch is turned to the ON and START positions.

      OK
      Ignition Switch Position Starter Signal
      ON OFF
      START ON
      Result
      Proceed to
      OK
      NG

    OK

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

    NG

  2. CHECK ST NO. 1 RELAY (POWER SOURCE)


    1. A01SJOLC01
      *1 Engine Room Relay Block Assembly
      *2 ST NO. 1 Relay

      Remove the ST NO. 1 relay from the engine room relay block assembly.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      ST NO. 1 relay terminal 2 - Body ground Engine cranking 11 to 14 V

      Tech Tips

      The engine does not crank because the relay is not installed.

      Result
      Result Proceed to
      OK A
      NG B

    B

    CHECK HARNESS AND CONNECTOR (ST NO. 1 RELAY - CLUTCH START SWITCH ASSEMBLY) Click here

    A

  3. INSPECT RELAY (ST NO. 1 RELAY)


    1. Inspect the ST NO. 1 relay.

      Click here

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE RELAY (ST NO. 1 RELAY)

    OK

  4. CHECK HARNESS AND CONNECTOR (ST NO. 2 RELAY - BODY GROUND)


    1. Remove the ST NO. 1 relay from the engine room relay block assembly.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      ST NO. 1 relay terminal 1 - Body ground Always Below 1 Ω
      Result
      Result Proceed to
      OK A
      NG B

    A

    REPAIR OR REPLACE HARNESS OR CONNECTOR (ECM - CLUTCH PEDAL SWITCH)

    B

    REPAIR OR REPLACE HARNESS OR CONNECTOR (ST NO. 1 RELAY - BODY GROUND)

  5. CHECK HARNESS AND CONNECTOR (ST NO. 1 RELAY - CLUTCH START SWITCH ASSEMBLY)


    1. Remove the ST NO. 1 relay from the engine room relay block assembly.

    2. Disconnect the clutch start switch assembly connector.

    3. Disconnect the ECM connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      ST NO. 1 relay terminal 2 - B2-1 Always Below 1 Ω
      ST NO. 1 relay terminal 2 - C53-17 (STA) Always Below 1 Ω
      ST NO. 1 relay terminal 2, B2-1 or C53-17 (STA) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  6. INSPECT CLUTCH START SWITCH ASSEMBLY


    1. Inspect the clutch start switch assembly.

      Click here

      Result
      Result
      OK
      NG

    NG

    REPLACE CLUTCH START SWITCH ASSEMBLY Click here

    OK

  7. CHECK HARNESS AND CONNECTOR (IGNITION SWITCH ASSEMBLY - CLUTCH START SWITCH ASSEMBLY)


    1. Disconnect the ignition or starter switch assembly connector.

    2. Disconnect the clutch start switch assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      G1-2 (ST2) - B2-2 Always Below 1 Ω
      G1-2 (ST2) or B2-2 - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  8. INSPECT IGNITION SWITCH ASSEMBLY


    1. Inspect the ignition switch assembly.

      Click here

      Result
      Proceed to
      OK
      NG

    OK

    REPAIR OR REPLACE HARNESS OR CONNECTOR (BATTERY - IGNITION SWITCH ASSEMBLY)

    NG

    REPLACE IGNITION SWITCH ASSEMBLY Click here