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Home >> Lexus >> 2012 >> IS 250 Base, AWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (Diagnostic Codes (P0630-U0101) & Circuit Tests) >> SFI System >> Circuit Tests >> Cranking Holding Function Circuit >> Procedure
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Cranking Holding Function Circuit: Procedure

  1. CHECK CRANKING 
    1. When starting the engine, check whether the starter motor starts.

      Result

      Result Proceed to
      NG A
      OK B

    B → See step   23 

    A: Go to next step 

  2. READ VALUE USING TECHSTREAM (STA SIGNAL) 
    1. Connect Techstream to the DLC3.
    2. Turn the engine switch on (IG) and turn the Techstream on.
    3. Enter the following menus: Powertrain / Engine / Data List / All Data / Starter Signal.
    4. Check the result when the engine switch is turned on (IG) and the engine is started.

      Standard

      Starter Signal Engine Switch Position
      Close (Starter signal off) On (IG)
      Open (Starter signal on) Engine start

      Result

      Result Proceed to
      NG A
      OK B

    B → See step   16 

    A: Go to next step 

  3. INSPECT ECM (STAR AND STSW VOLTAGE) 
    1. Measure the voltage according to the value(s) in the table below while cranking the engine.
      Fig 1: Identifying ECM Connectors
      GTY131166Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Voltage

      Tester Connection Condition Specified Condition
      E4-4 (STAR) - Body ground Cranking 5.5 V or more
      A5-19 (STSW) - Body ground Cranking 8 to 14 V

      Result

      Terminal STAR Terminal STSW Proceed to
      5.5 V or more 8 to 14 V A
      0 V 8 to 14 V B
      0 V 0 V C

    B → See step   24 

    C → See step   22 

    A: Go to next step 

  4. INSPECT ST CUT RELAY 
    1. Inspect the ST CUT relay. Refer to ON-VEHICLE INSPECTION .

      Result

      Result Proceed to
      OK (Automatic transmission models) A
      OK (Manual transmission models) B
      NG C

    B → See step   10 

    C → REPLACE ST CUT RELAY 

    A: Go to next step 

  5. INSPECT PARK/NEUTRAL POSITION SWITCH 
    1. Inspect the park/neutral position switch. Refer to INSPECTION for A760H.Refer to INSPECTION for A960E).

      Result

      Result Proceed to
      OK A
      NG (for A760H) B
      NG (for A960E) C

    B → See step   27 

    C → See step   29 

    A: Go to next step 

  6. CHECK HARNESS AND CONNECTOR (ST CUT RELAY POWER SOURCE) 
    1. Remove the ST CUT relay from the engine room R/B No. 2.
    2. Turn the engine switch on (IG).
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      ST CUT relay terminal 2 - Body ground Engine switch on (IG) 11 to 14 V
    4. Reinstall the ST CUT relay.

    NG → See step   15 

    OK: Go to next step 

  7. CHECK HARNESS AND CONNECTOR (ST CUT RELAY - BODY GROUND) 
    1. Remove the ST CUT relay from the engine room R/B No. 2.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for Open)

      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 

    OK: Go to next step 

  8. CHECK HARNESS AND CONNECTOR (ECM - ST CUT RELAY - POWER SOURCE CONTROL ECU) 
    1. Disconnect the E4 ECM connector.
    2. Remove the ST CUT relay from the engine room R/B No. 2.
    3. Disconnect the J55 power source control ECU connector.
    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for Open)

      Tester Connection Condition Specified Condition
      E4-4 (STAR) - ST CUT relay terminal 3 Always Below 1 Ω
      E4-4 (STAR) - J55-15 (STR2) Always Below 1 Ω

      Standard Resistance (Check for Short)

      Tester Connection Condition Specified Condition
      E4-4 (STAR) or ST CUT relay terminal 3 or J55-15 (STR2) - Body ground Always 10 kΩ or higher
    5. Reinstall the ST CUT relay.
    6. Reconnect the ECM connector.
    7. Reconnect the power source control ECU connector.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  9. CHECK HARNESS AND CONNECTOR (PNP SWITCH - ST CUT RELAY - POWER SOURCE CONTROL ECU) 
    1. Disconnect the E45 park/neutral position switch connector.
    2. Remove the ST CUT relay from the engine room R/B No. 2.
    3. Disconnect the J55 power source control ECU connector.
    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for Open)

      Tester Connection Condition Specified Condition
      E45-4 - ST CUT relay terminal 5 Always Below 1 Ω
      E45-4 - J55-17 (STR1) Always Below 1 Ω

      Standard Resistance (Check for Short)

      Tester Connection Condition Specified Condition
      E45-4 or ST CUT relay terminal 5 or J55-17 (STR1) - Body ground Always 10 kΩ or higher
    5. Reconnect the park/neutral position switch connector.
    6. Reinstall the ST CUT relay.
    7. Reconnect the power source control ECU connector.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

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

  10. INSPECT CLUTCH PEDAL SWITCH 
    1. Inspect the clutch pedal switch. Refer to INSPECTION .

    NG → See step   28 

    OK: Go to next step 

  11. CHECK HARNESS AND CONNECTOR (ST CUT RELAY POWER SOURCE) 
    1. Remove the ST CUT relay from the engine room R/B No. 2.
    2. Turn the engine switch on (IG).
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      ST CUT relay terminal 2 - Body ground Engine switch on (IG) 11 to 14 V
    4. Reinstall the ST CUT relay.

    NG → See step   15 

    OK: Go to next step 

  12. CHECK HARNESS AND CONNECTOR (ST CUT RELAY - BODY GROUND) 
    1. Remove the ST CUT relay from the engine room R/B No. 2.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for Open)

      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 

    OK: Go to next step 

  13. CHECK HARNESS AND CONNECTOR (ECM - ST CUT RELAY - POWER SOURCE CONTROL ECU) 
    1. Disconnect the E5 ECM connector.
    2. Remove the ST CUT relay from the engine room R/B No. 2.
    3. Disconnect the J55 power source control ECU connector.
    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for Open)

      Tester Connection Condition Specified Condition
      E4-4 (STAR) - ST CUT relay terminal 3 Always Below 1 Ω
      E4-4 (STAR) - J55-15 (STR2) Always Below 1 Ω

      Standard Resistance (Check for Short)

      Tester Connection Condition Specified Condition
      E4-4 (STAR) or ST CUT relay terminal 3 or J55-15 (STR2) - Body ground Always 10 kΩ or higher
    5. Reinstall the ST CUT relay.
    6. Reconnect the ECM connector.
    7. Reconnect the power source control ECU connector.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  14. CHECK HARNESS AND CONNECTOR (CLUTCH SWITCH - ST CUT RELAY - POWER SOURCE CONTROL ECU) 
    1. Disconnect the A24 clutch pedal switch connector.
    2. Remove the ST CUT relay from the engine room R/B No. 2.
    3. Disconnect the J55 power source control ECU connector.
    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for Open)

      Tester Connection Condition Specified Condition
      A24-1 - ST CUT relay terminal 5 Always Below 1 Ω
      A24-1 - J55-17 (STR1) Always Below 1 Ω

      Standard Resistance (Check for Short)

      Tester Connection Condition Specified Condition
      A24-1 or ST CUT relay terminal 5 or J55-17 (STR1) - Body ground Always 10 kΩ or higher
    5. Reconnect the clutch pedal switch connector.
    6. Reinstall the relay.
    7. Reconnect the power source control ECU connector.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → REPLACE HARNESS OR CONNECTOR (CLUTCH PEDAL SWITCH - ECM) 

  15. CHECK HARNESS AND CONNECTOR (ST CUT RELAY - POWER SOURCE CONTROL ECU) 
    1. Remove the ST CUT relay from the engine room R/B No. 2.
    2. Disconnect the J55 power source control ECU 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 CUT relay terminal 2 - J55-35 (IG2D) Always Below 1 Ω

      Standard Resistance (Check for Short)

      Tester Connection Condition Specified Condition
      ST CUT relay terminal 2 or J55-35 (IG2D) - Body ground Always 10 kΩ or higher
    4. Reinstall the ST CUT relay.
    5. Reconnect the power source control ECU connector.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → GO TO SMART ACCESS SYSTEM WITH PUSH-BUTTON START 

  16. INSPECT STARTER RELAY 
    1. Inspect the STARTER relay. Refer to ON-VEHICLE INSPECTION .

    NG → REPLACE STARTER RELAY 

    OK: Go to next step 

  17. CHECK HARNESS AND CONNECTOR (STARTER RELAY - BODY GROUND) 
    1. Remove the STARTER relay from the engine room R/B No. 1.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for Open)

      Tester Connection Condition Specified Condition
      STARTER relay terminal 2 - Body ground Always Below 1 Ω
    3. Reinstall the STARTER relay.

      Result

      Result Proceed to
      OK (Automatic transmission models) A
      OK (Manual transmission models) B
      NG C

    B → See step   19 

    C → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    A: Go to next step 

  18. CHECK HARNESS AND CONNECTOR (PARK/NEUTRAL POSITION SWITCH - STARTER RELAY) 
    1. Disconnect the E45 park/neutral position switch connector.
    2. Remove the STARTER relay from the engine room R/B No. 1.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for Open)

      Tester Connection Condition Specified Condition
      E45-5 - STARTER relay terminal 1 Always Below 1 Ω

      Standard Resistance (Check for Short)

      Tester Connection Condition Specified Condition
      E45-5 or STARTER relay terminal 1 - Body ground Always 10 kΩ or higher
    4. Reconnect the park/neutral position switch connector.
    5. Reinstall the STARTER relay.

      Result

      Result Proceed to
      NG A
      OK B

    B → See step   20 

    A → REPAIR OR REPLACE HARNESS OR CONNECTOR 

  19. CHECK HARNESS AND CONNECTOR (CLUTCH PEDAL SWITCH - STARTER RELAY) 
    1. Disconnect the A24 clutch pedal switch connector.
    2. Remove the STARTER relay from the engine room R/B No. 1.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for Open)

      Tester Connection Condition Specified Condition
      A24-2 - STARTER relay terminal 1 Always Below 1 Ω

      Standard Resistance (Check for Short)

      Tester Connection Condition Specified Condition
      A24-2 or STARTER relay terminal 1 - Body ground Always 10 kΩ or higher
    4. Reconnect the clutch pedal switch connector.
    5. Reinstall the relay.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  20. INSPECT ENGINE ROOM RELAY BLOCK NO. 1 (STARTER RELAY VOLTAGE) 
    1. Remove the STARTER relay from the engine room R/B No. 1.
      Fig 2: Identifying Starter Relay
      GTY141798Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      STARTER relay terminal 5 - Body ground Always 11 to 14 V
    3. Reinstall the STARTER relay.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (STARTER RELAY - BATTERY) 

    OK: Go to next step 

  21. INSPECT STARTER ASSEMBLY 
    1. Inspect the starter assembly. Refer to INSPECTION .

    NG → See step   25 

    OK → REPAIR OR REPLACE HARNESS AND CONNECTOR (STARTER RELAY - STARTER, STARTER - BATTERY) 

  22. CHECK HARNESS AND CONNECTOR (POWER SOURCE CONTROL ECU - ECM) 
    1. Disconnect the J55 power source control ECU connector.
    2. Disconnect the A5 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
      J55-39 (STSW) - A5-19 (STSW) Always Below 1 Ω

      Standard resistance (Check for Short)

      Tester Connection Condition Specified Condition
      J55-39 (STSW) or A5-19 (STSW) - Body ground Always 10 kΩ or higher
    4. Reconnect the ECM connector.
    5. Reconnect the power source control ECU connector.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   26 

  23. CHECK FOR INTERMITTENT PROBLEMS. Refer to  CHECK FOR INTERMITTENT PROBLEMS 
  24. REPLACE ECM. Refer to  REMOVAL 
  25. REPAIR OR REPLACE STARTER ASSEMBLY. Refer to  REMOVAL 
  26. GO TO SMART ACCESS SYSTEM WITH PUSH-BUTTON START. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING 
  27. REPLACE PARK/NEUTRAL POSITION SWITCH. Refer to  REMOVAL 
  28. REPLACE CLUTCH PEDAL SWITCH. Refer to  REMOVAL 
  29. REPLACE PARK/NEUTRAL POSITION SWITCH. Refer to  REMOVAL 
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