SFI SYSTEM Starter Signal Circuit

DTC Code DTC Name
Starter Signal Circuit

DESCRIPTION

  • w/o Entry and Start System

  • While the engine is being cranked, current flows from terminal ST2 of the ignition switch assembly to the ST CUT relay and also flows to terminal STA of the ECM (STA Signal). The ECM uses the STA signal to control the fuel injection and ignition timing when the engine starts.

  • w/ Entry and Start System

  • While the engine is being cranked, current flows from terminal STAR of the certification ECU (smart key ECU) to clutch pedal switch assembly and also flows to terminal STA of the ECM (STA signal).

WIRING DIAGRAM

A330560E01
A330561E01

CAUTION / NOTICE / HINT

Note:

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

PROCEDURE

  1. INSPECT ST RELAY

    1. Inspect the ST relay.

      Click here

    Result

    Proceed to

    OK

    NG
    NG

    REPLACE ST RELAY

    OK

  2. CHECK TERMINAL VOLTAGE (POWER SOURCE OF ST RELAY)

    1. Remove the ST relay from the No. 1 engine room relay block.

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

      Standard Voltage

      Tester Connection

      Condition

      Specified Condition

      5 (ST relay) - Body ground

      Always

      11 to 14 V

    Result

    Proceed to

    OK

    NG
    NG

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

    OK

  3. CHECK TERMINAL VOLTAGE (POWER SOURCE OF STARTER ASSEMBLY)

    1. Disconnect the starter assembly connector.

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

      Standard Voltage

      Tester Connection

      Condition

      Specified Condition

      C7-1 - Body ground

      Always

      11 to 14 V

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (STARTER ASSEMBLY - BATTERY)

    OK

  4. CHECK HARNESS AND CONNECTOR (ST RELAY - STARTER ASSEMBLY)

    1. Remove the ST relay from the No. 1 engine room relay block.

    2. Disconnect the starter assembly connector.

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      3 (ST relay) - C4-1

      Always

      Below 1 Ω

      3 (ST relay) or C4-1 - Body ground and other terminals

      Always

      10 kΩ or higher

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

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

    1. Remove the ST relay from the No. 1 engine room relay block.

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      1 (ST relay) - Body ground

      Always

      Below 1 Ω

    Result

    Result

    Proceed to

    OK (w/ Entry and Start System)

    A

    OK (w/o Entry and Start System)

    B

    NG

    C
    B

    CHECK HARNESS AND CONNECTOR (ST CUT RELAY - ST RELAY - ECM)Click here

    C

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    A

  6. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - ST RELAY - CLUTCH PEDAL SWITCH ASSEMBLY - ECM)

    1. Disconnect the certification ECU (smart key ECU assembly) connector.

    2. Remove the ST relay from the No. 1 engine room relay block.

    3. Disconnect the clutch pedal switch assembly connector.

    4. Disconnect the ECM connector.

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      E50-37 (STA) - B55-52 (STA)

      Always

      Below 1 Ω

      2 (ST relay) - B55-52 (STA)

      Always

      Below 1 Ω

      A19-1 - B55-52 (STA)

      Always

      Below 1 Ω

      E50-37 (STA), 2 (ST relay), A19-1 or B55-52 (STA) - Body ground and other terminals

      Always

      10 kΩ or higher

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  7. INSPECT CLUTCH PEDAL SWITCH ASSEMBLY

    1. Inspect the clutch pedal switch assembly.

      Click here

    Result

    Proceed to

    OK

    NG
    NG

    REPLACE CLUTCH PEDAL SWITCH ASSEMBLY

    Click here

    OK

  8. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU) - CLUTCH PEDAL SWITCH ASSEMBLY)

    1. Disconnect the certification ECU (smart key ECU) connector.

    2. Disconnect the clutch pedal switch assembly connector.

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      E50-16 (STAR) - A19-2

      Always

      Below 1 Ω

      E50-16 (STAR) or A19-2 - Body ground and other terminals

      Always

      10 kΩ or higher

    Result

    Proceed to

    OK

    NG
    OK

    GO TO ENTRY AND START SYSTEM

    Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  9. CHECK HARNESS AND CONNECTOR (ST CUT RELAY - ST RELAY - ECM)

    1. Remove the ST CUT relay from the center relay block.

    2. Remove the ST relay from the No. 1 engine room relay block.

    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

      4 (ST CUT relay) - B55-52 (STA)

      Always

      Below 1 Ω

      2 (ST relay) - B55-52 (STA)

      Always

      Below 1 Ω

      4 (ST CUT relay), 2 (ST relay) or B55-52 (STA) - Body ground and other terminals

      Always

      10 kΩ or higher

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  10. INSPECT IGNITION SWITCH ASSEMBLY

    1. Inspect the ignition switch assembly.

      Click here

    Result

    Proceed to

    OK

    NG
    NG

    REPLACE IGNITION SWITCH ASSEMBLY

    Click here

    OK

  11. INSPECT ST CUT RELAY

    1. Inspect the ST CUT relay.

      Click here

    Result

    Proceed to

    OK

    NG
    NG

    REPLACE ST CUT RELAY

    OK

  12. CHECK HARNESS AND CONNECTOR (IGNITION SWITCH ASSEMBLY - ST CUT RELAY)

    1. Disconnect the ignition switch assembly connector.

    2. Remove the ST CUT relay from the center relay block.

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      E21-7 (ST2) - 3 (ST CUT relay)

      Always

      Below 1 Ω

      E21-7 (ST2) or 3 (ST CUT relay) - Body ground and other terminals

      Always

      10 kΩ or higher

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  13. CHECK TERMINAL VOLTAGE (POWER SOURCE OF ST CUT RELAY)

    1. Remove the ST CUT relay from the center relay block.

    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

      1 (ST CUT relay) - Body ground

      Ignition switch ON

      11 to 14 V

    Result

    Proceed to

    OK

    NG
    NG

    CHECK HARNESS AND CONNECTOR (EFI MAIN RELAY - ST CUT RELAY)Click here

    OK

  14. CHECK HARNESS AND CONNECTOR (ST CUT RELAY - ECM)

    1. Remove the ST CUT relay from the center relay block.

    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

      2 (ST CUT relay) - B55-7 (STCT)

      Always

      Below 1 Ω

      2 (ST CUT relay) or B55-7 (STCT) - Body ground and other terminals

      Always

      10 kΩ or higher

    Result

    Proceed to

    OK

    NG
    OK

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

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  15. CHECK HARNESS AND CONNECTOR (EFI MAIN RELAY - ST CUT RELAY)

    1. Remove the EFI MAIN relay from the No. 1 engine room relay block.

    2. Remove the ST CUT relay from the center relay block.

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      5 (EFI MAIN relay) - 1 (ST CUT relay)

      Always

      Below 1 Ω

      5 (EFI MAIN relay) or 1 (ST CUT relay) - Body ground and other terminals

      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