SFI SYSTEM Starter Signal Circuit

DESCRIPTION

While the engine is being cranked, current flows from terminal ST1 of the ignition switch to the park/neutral position switch (for automatic transmission) or clutch start switch (for manual transmission) and also flows 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 inspection procedure.

Tech Tips

This chart is based on the premise that the engine can be cranked normally. If the engine does not crank normally, proceed to Problem Symptoms Table Click here.

PROCEDURE


  1. CHECK IF VEHICLE IS EQUIPPED WITH ENTRY AND START SYSTEM


    1. Confirm the vehicle specifications.

      Result
      Result Proceed to
      w/o Entry and Start System A
      w/ Entry and Start System B

    B

    READ VALUE USING GTS (STARTER SIGNAL) Click here

    A

  2. READ VALUE USING GTS


    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.

    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

    OK

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

    NG

  3. CHECK ST RELAY (POWER SOURCE)

    A01XCBHE01
    Text in Illustration
    *1 Engine Room Relay Block Assembly
    *2 ST Relay

    Remove the ST relay from the engine room relay block assembly.


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

      Standard Voltage
      Tester Connection Condition Specified Condition
      ST 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 (for Manual Transmission Models) B
      NG (for Automatic Transmission Models) C

    B

    CHECK HARNESS AND CONNECTOR (ST RELAY - CLUTCH START SWITCH ASSEMBLY, ECM) Click here

    C

    CHECK HARNESS AND CONNECTOR (PARK/NEUTRAL POSITION SWITCH ASSEMBLY - ST RELAY, ECM) Click here

    A

  4. INSPECT RELAY (ST RELAY)


    1. Inspect the ST relay Click here.


    NG

    REPLACE RELAY (ST RELAY)

    OK

  5. CHECK HARNESS AND CONNECTOR (ST RELAY - BODY GROUND)


    1. Remove the ST 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 relay terminal 1 - Body ground Always Below 1 Ω
      Result
      Result Proceed to
      OK (for Manual Transmission Models) A
      OK (for Automatic Transmission Models) B
      NG C

    A

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

    B

    REPAIR OR REPLACE HARNESS OR CONNECTOR (ECM - PARK/NEUTRAL POSITION SWITCH)

    C

    REPAIR OR REPLACE HARNESS OR CONNECTOR (ST RELAY - BODY GROUND)

  6. CHECK HARNESS AND CONNECTOR (ST RELAY - CLUTCH START SWITCH ASSEMBLY, ECM)


    1. Remove the ST 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 relay terminal 2 - A41-1 Always Below 1 Ω
      ST relay terminal 2 - C154-17 (STA) Always Below 1 Ω
      ST relay terminal 2, A41-1 or C154-17 (STA) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  7. INSPECT CLUTCH START SWITCH ASSEMBLY


    1. Inspect the clutch start switch assembly (See page) Click here.


    NG

    REPLACE CLUTCH START SWITCH ASSEMBLY Click here

    OK

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


    1. Disconnect the ignition 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
      G2-1 (ST1) - A41-2 Always Below 1 Ω
      G2-1 (ST1) or A41-2 - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  9. INSPECT IGNITION OR STARTER SWITCH ASSEMBLY


    1. Inspect the ignition switch assembly ( Click here).


    OK

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

    NG

    REPLACE IGNITION OR STARTER SWITCH ASSEMBLY Click here

  10. CHECK HARNESS AND CONNECTOR (PARK/NEUTRAL POSITION SWITCH ASSEMBLY - ST RELAY, ECM)


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

    2. Disconnect the park/neutral position 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
      C159-5 (L) - ST relay terminal 2 Always Below 1 Ω
      C154-17 (STA) - ST relay terminal 2 Always Below 1 Ω
      C159-5 (L), C154-17 (STA) or ST relay terminal 2 - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  11. INSPECT PARK/NEUTRAL POSITION SWITCH ASSEMBLY


    1. Inspect the park/neutral position switch assembly Click here.


    NG

    REPLACE PARK/NEUTRAL POSITION SWITCH ASSEMBLY Click here

    OK

  12. CHECK HARNESS AND CONNECTOR (IGNITION SWITCH ASSEMBLY - PARK/NEUTRAL POSITION SWITCH ASSEMBLY, ECM)


    1. Disconnect the park/neutral position switch assembly connector.

    2. Disconnect the ignition 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
      G2-1 (ST1) - C159-4 (B) Always Below 1 Ω
      G2-1 (ST1) - C154-15 (NSW) Always Below 1 Ω
      G2-1 (ST1), C159-4 (B) or C154-15 (NSW) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  13. INSPECT IGNITION OR STARTER SWITCH ASSEMBLY


    1. Inspect the ignition switch assembly Click here.


    OK

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

    NG

    REPLACE IGNITION OR STARTER SWITCH ASSEMBLY Click here

  14. 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.

    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
      Result Proceed to
      NG A
      OK B

    B

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

    A

  15. INSPECT PARK/NEUTRAL POSITION SWITCH ASSEMBLY


    1. Inspect the park/neutral position switch assembly Click here.


    NG

    REPLACE PARK/NEUTRAL POSITION SWITCH ASSEMBLY Click here

    OK

  16. CHECK HARNESS AND CONNECTOR (ST RELAY - PARK/NEUTRAL POSITION SWITCH ASSEMBLY, ECM)


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

    2. Disconnect the park/neutral position switch assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      ST relay terminal 2 - C159-5(L) Always Below 1 Ω
      ST relay terminal 2 - C154-17 (STA) Always Below 1 Ω
      ST relay terminal 2, C159-5 (L) or C154-17 (STA) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  17. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU - PARK/NEUTRAL POSITION SWITCH ASSEMBLY, ECM)


    1. Disconnect the park/neutral position switch assembly connector.

    2. Disconnect the certification ECU (smart key ECU 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
      G50-3 (STAR) - C159-4 (B) Always Below 1 Ω
      G50-3 (STAR) - C154-15 (NSW) Always Below 1 Ω
      G50-3 (STAR) or C159-4 (B) or C154-15 (NSW) - Body ground Always 10 kΩ or higher

    OK

    GO TO ENTRY AND START SYSTEM Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR