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Home >> Lexus >> 2008 >> LX 570 >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - System Descriptions And Testing, On-Vehicle Inspection, Removal And Installation >> Cranking Holding Function Circuit >> Inspection Procedure
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Inspection Procedure

  1. CHECK CRANKING 
    1. Check the cranking of the engine.

      Result 

    RESULT REFERENCE

    Result Proceed to
    Cranking possible and holding control operates A
    Does not crank B
    Cranking possible but holding control does not operate C

    B:  Go to step  2

    C:  Go to step  11

    A: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE  (See PROBLEM SYMPTOMS TABLE )

  2. READ VALUE USING TECHSTREAM (STARTER SIGNAL) 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Powertrain / Engine and ECT / Data List / Starter Signal.
    5. Check the value displayed on the Techstream when the engine switch is turned to the START.

    Standard 

    DATA LIST

    Engine Switch Position Display (Starter Signal)
    On (IG) OFF
    START ON

    NG:  Go to step  7

    OK: Go to Next Step 

  3. INSPECT STARTER RELAY (ST) 
    1. Remove the starter relay (ST) from the engine room relay block.
    2. Measure the resistance according to the value(s) in the table below.

    Standard Resistance 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    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 terminals 1 and 2 Below 1 Ω

    NG: REPLACE STARTER RELAY (ST) 

    Fig 1: Inserting Starter Relay (ST)
    G04942976Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to Next Step 

  4. CHECK HARNESS AND CONNECTOR (ST RELAY - PNP SWITCH) 
    1. Remove the starter relay (ST) from the engine room relay block.
    2. Disconnect the C19 PNP switch.
    3. Measure the resistance according to the value(s) in the table below.

    Standard Resistance 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    ST relay (1) - C19-5 Always Below 1 Ω
    ST relay (1) or C19-5-Body ground Always 10 kΩ or higher

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 2: Identifying Terminals Of C19 PNP Switch
    G05628182Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to Next Step 

  5. CHECK STARTER RELAY (POWER SOURCE) 
    1. 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 SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    ST relay (2) - ST relay (5) Always 11 to 14 V

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (STARTER RELAY (ST) BATTERY, BODY GROUND) 

    Fig 3: Identifying Terminals Of ST Relay
    G05149980Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to Next Step 

  6. INSPECT STARTER 
    1. Inspect the starter (See INSPECTION ).

    NG: REPAIR OR REPLACE STARTER  (See REMOVAL )

    OK: REPAIR OR REPLACE HARNESS OR CONNECTOR (STARTER - STARTER RELAY (ST), BATTERY) 

  7. INSPECT STARTER CUT RELAY (ST CUT) 
    1. Remove the starter cut relay (ST CUT) from the engine room relay block.
    2. Measure the resistance according to the value(s) in the table below.

    Standard Resistance 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    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 terminals 1 and 2 Below 1 Ω

    NG: REPLACE STARTER CUT RELAY (ST CUT) 

    Fig 4: Inserting Starter Cut Relay (ST CUT)
    G04942976Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to Next Step 

  8. CHECK HARNESS AND CONNECTOR (ST CUT RELAY - PNP SWITCH, ECM) 
    1. Remove the starter cut relay (ST CUT) from the engine room relay block.
    2. Disconnect the C19 PNP switch connector.
    3. Disconnect the C53 ECM connector.
    4. Measure the resistance according to the value(s) in the table below.

    Standard Resistance 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    ST CUT relay (5) - C53-16 (STAR) Always Below 1 Ω
    ST CUT relay (3) - C19-4 Always Below 1 Ω
    ST CUT relay (5) or C53-16 (STAR) - Body ground Always 10 kΩ or higher
    ST CUT relay (3) or C19-4 - Body ground Always 10 kΩ or higher

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 5: Identifying Terminals Of C19 PNP Switch And C53 ECM Connectors
    G05628185Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to Next Step 

  9. INSPECT PARK/NEUTRAL POSITION SWITCH 
    1. Inspect the Park/Neutral Position (PNP) switch.
      1. Disconnect the C19 PNP switch connector.
      2. Measure the resistance according to the value(s) in the table below.

    Standard Resistance 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Switch Condition Specified Condition
    4(B) - 5(L) Shift lever in P Below 1 Ω
    Shift lever in N Below 1 Ω

    NG: REPLACE PARK/NEUTRAL POSITION SWITCH  (See ON-VEHICLE INSPECTION )

    Fig 6: Identifying Terminals Of C19 PNP Switch Connector
    G05628040Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to Next Step 

  10. CHECK HARNESS AND CONNECTOR (PNP SWITCH - ECM) 
    1. Disconnect the C19 PNP switch connector.
    2. Disconnect the A38 ECM connector.
    3. Measure the resistance according to the value(s) in the table below.

    Standard Resistance 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    C19-5 - A38-46(STA) Always Below 1 Ω
    C19-5 or A38-46(STA) - Body ground Always 10 kΩ or higher

    Result 

    RESULT REFERENCE

    Result Proceed to
    NG A
    OK B

    B:  Go to step  13

    Fig 7: Identifying Terminals Of C19 PNP Switch And A38 ECM Connectors
    G05628041Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    A: REPAIR OR REPLACE HARNESS OR CONNECTOR 

  11. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - ECM) 
    Fig 8: Identifying Terminals Of E4 Main Body ECU And A38 ECM Connectors
    G05630975Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the E4 main body ECU connector.
    2. Disconnect the A38 ECM connector.
    3. Measure the resistance according to the value(s) in the table below.

    Standard Resistance 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    E4-4 (STSW) - A38-14 (STSW) Always Below 1 Ω
    E4-4(STSW) or A38-14 (STSW) - Body ground Always 10 kΩ or higher

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to Next Step 

  12. CHECK HARNESS AND CONNECTOR (ST CUT RELAY - PNP SWITCH, ECM) 
    1. Remove the starter cut relay (ST CUT) from the engine room relay block.
    2. Disconnect the C19 PNP switch connector.
    3. Disconnect the C53 ECM connector.
    4. Measure the resistance according to the value(s) in the table below.

    Standard Resistance 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Condition Specified Condition
    ST CUT relay (5) - C53-16 (STAR) Always Below 1 Ω
    ST CUT relay (3) - C19-4 Always Below 1 Ω
    ST CUT relay (5) or C53-16 (STAR) - Body ground Always 10 kΩ or higher
    ST CUT relay (3) or C19-4 - Body ground Always 10 kΩ or higher

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 9: Identifying Terminals Of C19 PNP Switch And C53 ECM Connectors
    G05628185Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: REPLACE ECM  (See ECM )

  13. REPLACE ECM 
    1. Replace the ECM (See ECM ).
  14. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED 
    1. Check the starter operation.

      OK: Malfunction has been repaired successfully. 

    NG: GO TO SMART ACCESS SYSTEM WITH PUSH-BUTTON START (ENGINE DOES NOT START)  (See ENGINE DOES NOT START )

    OK: END 

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