SFI SYSTEM Cranking Holding Function Circuit

DESCRIPTION

The cranking holding control system provides current to the starter assembly when the ECM detects the engine switch start signal (STSW). When the ECM judges that the engine has started, the system cuts current to the starter assembly. When the ECM receives the STSW signal, the ACC (Accessory) relay is turned off to prevent flickering of the combination meter assembly, clock and audio system. Also, the STAR output signal travels through the ST CUT relay and the park/neutral position switch assembly to the ST relay, causing the starter assembly to activate.

When the engine is cranking, the starter operation signal is received by the STA terminal of the ECM.

A017CMCE02

WIRING DIAGRAM

Refer to DTC P0617 Click here.

INSPECTION PROCEDURE

Note

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

PROCEDURE


  1. READ VALUE USING INTELLIGENT TESTER (STARTER SIGNAL)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the engine switch on (IG) and turn the tester on.

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

    4. Check the result when the engine switch is turned to the ON.

    5. Check the result when the engine starts.

      OK
      Engine Switch Position Tester Display (Starter Signal)
      on (IG) Close (Starter signal off)
      START Open (Starter signal on)
      Result
      Result Proceed to
      NG A
      OK B

    B

    CHECK ST RELAY (INPUT VOLTAGE) Click here

    A

  2. CHECK ECM (STSW TERMINAL VOLTAGE)


    1. A017G3PE23
      Text in Illustration
      *a

      Component with harness connected

      (ECM)

      Move the shift lever to neutral.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      D55-30 (STSW) - Body ground Engine cranking 11 to 14 V

    NG

    CHECK HARNESS AND CONNECTOR (ECM - MAIN BODY ECU) Click here

    OK

  3. CHECK PARK/NEUTRAL POSITION SWITCH ASSEMBLY (INPUT VOLTAGE)


    1. A017BXKE13
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Park/Neutral Position Switch Assembly)

      Disconnect the park/neutral position switch assembly connector.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      B5-4 - Body ground Engine cranking 11 to 14 V

    3. Reconnect the park/neutral position switch assembly connector.


    NG

    INSPECT ST CUT RELAY Click here

    OK

  4. INSPECT PARK/NEUTRAL POSITION SWITCH ASSEMBLY


    1. Inspect the park/neutral position switch assembly Click here for U151E, Click here for U151F).

      Result
      Result Proceed to
      OK A
      NG (for U151E) B
      NG (for U151F C

    B

    REPLACE PARK/NEUTRAL POSITION SWITCH ASSEMBLY Click here

    C

    REPLACE PARK/NEUTRAL POSITION SWITCH ASSEMBLY Click here

    A

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

  5. CHECK HARNESS AND CONNECTOR (ECM - MAIN BODY ECU)


    1. Disconnect the main body ECM connector.

    2. Disconnect the ECM connector.

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

      Standard Resistance (Check for Open)
      Tester Connection Condition Specified Condition
      D9-4 (STSW) - D55-30 (STSW) Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      D9-4 (STSW) or D55-30 (STSW) - Body ground Always 10 kΩ or higher

    4. Reconnect the main body ECU connector.

    5. Reconnect the ECM connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (ECM - MAIN BODY ECU)

    OK

    CHECK SMART ENTRY AND START SYSTEM Click here

  6. INSPECT ST CUT RELAY


    1. A017BXOE01

      Remove the ST CUT 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
      3 - 5 No battery voltage applied to terminals 1 and 2 10 kΩ or higher
      3 - 5 Battery voltage applied to between terminals 1 and 2 Below 1 Ω

    3. Reinstall the relay.


    NG

    REPLACE ST CUT RELAY

    OK

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


    1. Remove the ST CUT 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
      ST CUT relay terminal 1 - Body ground Always Below 1 Ω

    3. Reinstall the ST CUT relay.


    NG

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

    OK

  8. CHECK HARNESS AND CONNECTOR (ST CUT RELAY - IG2 RELAY)


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

    2. Remove the IG2 relay from the engine room relay block.

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

      Standard Resistance (Check for Open)
      Tester Connection Condition Specified Condition
      IG2 relay terminal 3 - ST CUT relay terminal 2 Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      IG2 relay terminal 3 or ST CUT relay terminal 2 - Body ground Always 10 kΩ or higher

    4. Reinstall the ST CUT relay.

    5. Reinstall the IG2 relay.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (ST CUT RELAY - IG2 RELAY)

    OK

  9. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - PNP SWITCH - ECM - ST CUT RELAY)


    1. Remove the ST CUT relay from the No. 6 relay block.

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

    3. Disconnect the ECM connector.

    4. Disconnect the main body ECU connector.

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

      Standard Resistance (Check for Open)
      Tester Connection Condition Specified Condition
      D9-6 (STR2) - ST CUT relay terminal 5 Always Below 1 Ω
      D9-6 (STR2) - B48-31 (STAR) Always Below 1 Ω
      D7-8 (STR) - ST CUT relay terminal 3 Always Below 1 Ω
      D7-8 (STR) - B49-2 (NSW) Always Below 1 Ω
      D7-8 (STR) - B5-4 Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      D9-6 (STR2) or ST CUT relay terminal 5 or B48-31 (STAR) or ST CUT relay terminal 3 or D7-8 (STR) or B49-2 (NSW) or B5-4 - Body ground Always 10 kΩ or higher

    6. Reinstall the ST CUT relay.

    7. Reconnect the park/neutral position switch assembly connector.

    8. Reconnect the ECM connector.

    9. Reconnect the main body ECU connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (MAIN BODY ECU - PNP SWITCH - ECM - ST CUT RELAY)

    OK

    REPLACE ECM Click here

  10. CHECK ST RELAY (INPUT VOLTAGE)


    1. A017EV2E04
      Text in Illustration
      *1 Engine Room Relay Block

      Remove the ST relay from the engine room relay block.

    2. 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

    3. Reinstall the ST relay.


    NG

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

    OK

  11. INSPECT ST RELAY


    1. A017BXOE01

      Remove the ST 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
      3 - 5 No battery voltage applied to terminals 1 and 2 10 kΩ or higher
      3 - 5 Battery voltage applied to between terminals 1 and 2 Below 1 Ω

    3. Reinstall the ST relay.


    NG

    REPLACE ST RELAY

    OK

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


    1. Remove the ST 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
      ST relay terminal 1 - Body ground Always Below 1 Ω

    3. Reinstall the ST relay.


    NG

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

    OK

  13. CHECK ST RELAY (INPUT VOLTAGE)


    1. A017EV2E04
      Text in Illustration
      *1 Engine Room Relay Block

      Remove the ST relay from the engine room relay block.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      ST relay terminal 5 - Body ground Always 11 to 14 V

    3. Reinstall the ST relay.


    NG

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

    OK

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


    1. Remove the ST relay from the 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 (Check for Open)
      Tester Connection Condition Specified Condition
      ST relay terminal 3 - B12-1 Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      ST relay terminal 3 or B12-1 - Body ground Always 10 kΩ or higher

    4. Reinstall the ST relay.

    5. Reconnect the starter assembly connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (ST RELAY - STARTER ASSEMBLY)

    OK

  15. INSPECT STARTER ASSEMBLY


    1. Inspect the starter assembly Click here.


    NG

    REPLACE STARTER ASSEMBLY Click here

    OK

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