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Home >> Lexus >> 2011 >> IS 250C Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (4GR-FSE) (Diagnostic Codes & Circuit Tests) >> SFI System >> Circuit Tests >> Cranking Holding Function Circuit >> Procedure
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Cranking Holding Function Circuit: Procedure

  1. READ VALUE USING TECHSTREAM (STA SIGNAL) 
    1. Connect the 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

    NG → See step   9 

    OK: Go to next step 

  2. INSPECT STARTER RELAY 
    1. Remove the STARTER relay from the engine room relay block No. 1.
      Fig 1: Identifying Relay Test Terminals
      GTY102844Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    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 across terminals 1 and 2 10 kΩ or higher
      3 - 5 Battery voltage applied across terminals 1 and 2 Below 1 Ω
    3. Reinstall the STARTER relay.

    NG → REPLACE STARTER RELAY 

    OK: Go to next step 

  3. CHECK HARNESS AND CONNECTOR (STARTER RELAY - BODY GROUND) 
    1. Remove the STARTER relay from the engine room relay block 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 (for Automatic transmission models) A
      OK (for Manual transmission models) B
      NG C

    B → See step   5 

    C → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    A: Go to next step 

  4. CHECK HARNESS AND CONNECTOR (PARK/NEUTRAL POSITION SWITCH - STARTER RELAY) 
    1. Disconnect the park/neutral position switch connector.
    2. Remove the STARTER relay from the engine room relay block 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   6 

    A → REPAIR OR REPLACE HARNESS OR CONNECTOR 

  5. CHECK HARNESS AND CONNECTOR (CLUTCH PEDAL SWITCH - STARTER RELAY) 
    1. Disconnect the clutch pedal switch connector.
    2. Remove the STARTER relay from the engine room relay block 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 

  6. INSPECT ENGINE ROOM RELAY BLOCK NO. 1 (STARTER RELAY VOLTAGE) 
    1. Remove the STARTER relay from the engine room relay block No. 1.
      Fig 2: Identifying Engine Room No. 1 Relay Block
      GTY284349Courtesy 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
      TEXT IN ILLUSTRATION

      *1 Engine Room Relay Block No. 1
    3. Reinstall the STARTER relay.

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

    OK: Go to next step 

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

    NG → See step   25 

    OK: Go to next step 

  8. CHECK HARNESS AND CONNECTOR (STARTER RELAY - STARTER ASSEMBLY) 
    1. Remove the STARTER relay from the engine room relay block No. 1.
    2. Disconnect the starter connector.
    3. 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 3 - E10-1 Always Below 1 Ω

      Standard Resistance (Check for Short)

      Tester Connection Condition Specified Condition
      STARTER relay terminal 3 or E10-1 - Body ground Always 10 kΩ or higher
    4. Reinstall the STARTER relay.
    5. Reconnect the starter connector.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

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

  9. INSPECT ECM (STAR AND STSW VOLTAGE) 
    1. Measure the voltage according to the value(s) in the table below while cranking the engine.
      Fig 3: E4 & A5 Connector
      GTY354068Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Voltage

      Tester Connection Condition Specified Condition
      E4-4 (STAR) - Body ground Cranking 11 to 14 V
      A5-19 (STSW) - Body ground Cranking 11 to 14 V
      TEXT IN ILLUSTRATION

      *a Component with harness connected
      (ECM)

      Result

      Terminal STAR Terminal STSW Proceed to
      11 to 14 V 11 to 14 V A
      0 V 11 to 14 V B
      0 V 0 V C

    B → See step   26 

    C → See step   22 

    A: Go to next step 

  10. INSPECT ST CUT RELAY 
    1. Remove the ST CUT relay from the engine room relay block No. 2.
      Fig 4: Identifying Relay Test Terminals
      GTY100961Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    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 across terminals 1 and 2 10 kΩ or higher
      3 - 5 Battery voltage applied across terminals 1 and 2 Below 1 Ω
    3. Reinstall the ST CUT relay.

      Result

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

    B → See step   16 

    C → REPLACE ST CUT RELAY 

    A: Go to next step 

  11. INSPECT PARK/NEUTRAL POSITION SWITCH ASSEMBLY 
    1. Inspect the park/neutral position switch. Refer to INSPECTION .

    NG → See step   23 

    OK: Go to next step 

  12. CHECK HARNESS AND CONNECTOR (ST CUT RELAY POWER SOURCE) 
    1. Remove the ST CUT relay from the engine room relay block 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   21 

    OK: Go to next step 

  13. CHECK HARNESS AND CONNECTOR (ST CUT RELAY - BODY GROUND) 
    1. Remove the ST CUT relay from the engine room relay block 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 

  14. CHECK HARNESS AND CONNECTOR (ECM - ST CUT RELAY - POWER SOURCE CONTROL ECU) 
    1. Disconnect the ECM connector.
    2. Remove the ST CUT relay from the engine room relay block No. 2.
    3. Disconnect the 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 

  15. CHECK HARNESS AND CONNECTOR (PNP SWITCH - ST CUT RELAY - POWER SOURCE CONTROL ECU) 
    1. Disconnect the park/neutral position switch connector.
    2. Remove the ST CUT relay from the engine room relay block No. 2.
    3. Disconnect the 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) 

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

    NG → See step   27 

    OK: Go to next step 

  17. CHECK HARNESS AND CONNECTOR (ST CUT RELAY POWER SOURCE) 
    1. Remove the ST CUT relay from the engine room relay block 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   21 

    OK: Go to next step 

  18. CHECK HARNESS AND CONNECTOR (ST CUT RELAY - BODY GROUND) 
    1. Remove the ST CUT relay from the engine room relay block 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 

  19. CHECK HARNESS AND CONNECTOR (ECM - ST CUT RELAY - POWER SOURCE CONTROL ECU) 
    1. Disconnect the ECM connector.
    2. Remove the ST CUT relay from the engine room relay block No. 2.
    3. Disconnect the 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 

  20. CHECK HARNESS AND CONNECTOR (CLUTCH SWITCH - ST CUT RELAY - POWER SOURCE CONTROL ECU) 
    1. Disconnect the clutch pedal switch connector.
    2. Remove the ST CUT relay from the engine room relay block No. 2.
    3. Disconnect the 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.

    MG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

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

  21. CHECK HARNESS AND CONNECTOR (ST CUT RELAY - POWER SOURCE CONTROL ECU) 
    1. Remove the ST CUT relay from the engine room relay block No. 2.
    2. Disconnect the 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 → See step   24 

  22. CHECK HARNESS AND CONNECTOR (POWER SOURCE CONTROL ECU - ECM) 
    1. Disconnect the power source control ECU 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
      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   24 

  23. REPLACE PARK/NEUTRAL POSITION SWITCH ASSEMBLY. Refer to  REMOVAL 
  24. GO TO SMART ACCESS SYSTEM WITH PUSH-BUTTON START. Refer to  ON-VEHICLE INSPECTION 
  25. REPLACE STARTER ASSEMBLY. Refer to  REMOVAL 
  26. REPLACE ECM. Refer to  REMOVAL 
  27. REPLACE CLUTCH PEDAL SWITCH. Refer to  REMOVAL 
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