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Home >> Lexus >> 2013 >> IS F >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (Diagnostic Codes (P1603 - U0101) & 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 / Starter Signal.
    4. Check the result when the engine switch is turned on (IG) and the engine is started.

      Standard

      Condition Techstream Display
      Engine switch on (IG) OFF
      Engine started ON

    NG → See step   9 

    OK: Go to next step 

  2. INSPECT STARTER RELAY 
    1. Inspect the STARTER relay. Refer to ON-VEHICLE INSPECTION [08/2012 - ] - Step 1 .

    NG → REPLACE STARTER RELAY 

    OK: Go to next step 

  3. INSPECT FUSIBLE LINK BLOCK ASSEMBLY (STARTER FUSE) 
    1. Remove the fusible link block assembly from the engine room No. 1 relay block.
      GTY120979Courtesy 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
      1B-1 - 1G-4 Always Below 1 Ω

    NG → REPLACE FUSIBLE LINK BLOCK ASSEMBLY (STARTER FUSE) 

    OK: 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 No. 1 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
      E45-5 (L) - STARTER relay (1) Always Below 1 Ω

      Standard Resistance (Check for Short)

      Tester Connection Condition Specified Condition
      E45-5 (L) or STARTER relay (1) - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

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

      Standard Resistance

      Tester Connection Condition Specified Condition
      STARTER relay (2) - Body ground Always Below 1 Ω

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

    OK: Go to next step 

  6. INSPECT ENGINE ROOM RELAY BLOCK (STARTER RELAY VOLTAGE) 
    1. Remove the STARTER relay from the engine room No. 1 relay block.
      GTY105670Courtesy 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 (5) - Body ground Always 11 to 14 V

    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 [08/2012 - ] .

    NG → See step   21 

    OK: Go to next step 

  8. CHECK HARNESS AND CONNECTOR (STARTER RELAY - STARTER ASSEMBLY) 
    1. Remove the STARTER relay from the engine room No. 1 relay block.
    2. Disconnect the starter connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      STARTER relay (3) - E10-1 Always Below 1 Ω

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

    OK → REPAIR OR REPLACE HARNESS OR CONNECTOR (STARTER - 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.
      GTY146231Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Voltage

      Tester Connection Condition Specified Condition
      A5-2 (STAR) - E6-1 (E1) Cranking 5.5 V or more
      A5-27 (STSW) - E6-1 (E1) Cranking 8.0 to 14 V

      Result

      Terminal STAR Terminal STSW Proceed to
      5.5 V or more 8.0 to 14 V A
      0 V 8.0 to 14 V B
      0 V 0 V C

    B → See step   22 

    C → See step   17 

    A: Go to next step 

  10. INSPECT ST CUT RELAY 
    1. Inspect the ST CUT relay. Refer to ON-VEHICLE INSPECTION [08/2012 - ] - Step 2 .

    NG → REPLACE ST CUT RELAY 

    OK: Go to next step 

  11. INSPECT PARK/NEUTRAL POSITION SWITCH ASSEMBLY 
    1. Inspect the park/neutral position switch assembly. Refer to INSPECTION [08/2012 - ] .

    NG → See step   19 

    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 No. 2 relay block.
    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 (2) - Body ground Engine switch on (IG) 11 to 14 V

    NG → See step   16 

    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 No. 2 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 (1) - Body ground Always Below 1 Ω

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  14. CHECK HARNESS AND CONNECTOR (ECM - ST CUT RELAY) 
    1. Disconnect the ECM connector.
    2. Remove the ST CUT relay from the engine room No. 2 relay block.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A5-2 (STAR) - ST CUT relay (3) Always Below 1 Ω

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  15. CHECK HARNESS AND CONNECTOR (PARK/NEUTRAL POSITION SWITCH - ST CUT RELAY) 
    1. Disconnect the park/neutral position switch connector.
    2. Remove the ST CUT relay from the engine room No. 2 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
      E45-4 (B) - ST CUT relay (5) Always Below 1 Ω

      Standard Resistance (Check for Short)

      Tester Connection Condition Specified Condition
      E45-4 (B) or ST CUT relay (5) - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (ST CUT RELAY - PARK/NEUTRAL POSITION SWITCH) 

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

  16. CHECK HARNESS AND CONNECTOR (ST CUT RELAY - POWER SOURCE CONTROL ECU) 
    1. Remove the ST CUT relay from the engine room No. 2 relay block.
    2. Disconnect the power source control ECU connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      ST CUT relay (2) - J55-35 (IG2D) Always Below 1 Ω

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   20 

  17. CHECK HARNESS AND CONNECTOR (POWER SOURCE CONTROL ECU - ECM) 
    1. Check the harness and the connectors between the power source control ECU and 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) - A5-27 (STSW) Always Below 1 Ω

        Standard Resistance (Check for Short)

        Tester Connection Condition Specified Condition
        J55-39 (STSW) or A5-27 (STSW) - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   18 

  18. GO TO SMART ACCESS SYSTEM WITH PUSH-BUTTON START. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [08/2012 - ] 
  19. REPLACE PARK/NEUTRAL POSITION SWITCH ASSEMBLY. Refer to  REMOVAL [08/2012 - ] 
  20. GO TO SMART ACCESS SYSTEM WITH PUSH-BUTTON START. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [08/2012 - ] 
  21. REPLACE STARTER ASSEMBLY. Refer to  REMOVAL [08/2012 - ] 
  22. REPLACE ECM. Refer to  REMOVAL [08/2012 - ] 
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