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Home >> Lexus >> 2007 >> GS 430 >> Repair and Diagnosis >> Engine Performance >> Engine Control System (3UZ-FE) >> SFI System >> Cranking Holding Function Circuit >> Inspection Procedure
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Inspection Procedure

  1. CHECK OPERATION OF ENGINE CRANKING 
    1. When turning the engine switch to start, check whether the starter motor starts.

    OK: CHECK FOR INTERMITTENT PROBLEMS 

    NG: Go to next step 

  2. READ DATA LIST (STARTER SIGNAL) 
    1. Connect the intelligent tester to the CAN VIM. Then connect the CAN VIM to the DLC3.
    2. Enter the following menu: DIAGNOSIS / ENHANCED OBD II / DATA LIST / PRIMARY / STARTER SIG.
    3. Confirm the starter signal status when the engine switch is operated.

    OK 

    ENGINE SWITCH POSITION CHART

    Engine Switch Position STARTER SIG
    On (IG) OFF
    Start ON

    OK:  Go to step  6

    NG: Go to next step 

  3. CHECK ECM (STSW AND STAR VOLTAGE) 
    1. Measure the voltage of the A6 and E7 ECM connectors.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Specified Condition
      A6-19 (STSW) - E7-7 (E1) 9 to 14 V
      E7-4 (STAR) - E7-7 (E1) 9 to 14 V
    Fig 1: Checking ECM (STSW And STAR Voltage)
    G05285739Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    Result 

    RESULT CHART

    Terminal STSW Terminal STAR Proceed to
    9 to 14 V 9 to 14 V A
    9 to 14 V 0 V B
    0 V 0 V C

    B: REPLACE ECM 

    C:  Go to step  10

    A: Go to next step 

  4. INSPECT RELAY (Marking: ST CUT) 
    1. Remove the starter cut relay from engine room No. 2 relay block.
    2. Measure the resistance of the relay.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Specified Condition
      3-5 10 kΩ or higher
      3-5 Below 1 Ω
      (when battery voltage is applied to terminals 1 and 2)
    Fig 2: Identifying ST CUT Relay
    G05285740Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE RELAY 

    OK: Go to next step 

  5. INSPECT PARK/NEUTRAL POSITION SWITCH 
    1. Move the shift lever to the P or N position.
    2. Disconnect the E25 PNP switch connector.
    3. Measure the resistance of the PNP switch.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Shift Position Tester Connection Specified Condition
      P or N 9 - 6 Below 1 Ω
    Fig 3: Identifying PNP Switch Connector Terminals
    G05285644Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE PARK/NEUTRAL POSITION SWITCH 

    OK: REPAIR OR REPLACE HARNESS AND CONNECTOR (PARK / NEUTRAL POSITION SWITCH - ECM, ECM - ST CUT RELAY, ST CUT RELAY - PARK / NEUTRAL POSITION SWITCH) 

  6. INSPECT RELAY (Marking: STARTER) 
    1. Remove the starter relay from engine room No. 1 relay block.
    2. Measure the resistance of the relay.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Specified Condition
      3 - 5 10 kΩ or higher
      3 - 5 Below 1 Ω
      (when battery voltage is applied to terminals 1 and 2)
    Fig 4: Identifying Starter Relay
    G05285742Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE RELAY 

    OK: Go to next step 

  7. CHECK WIRE HARNESS (PARK / NEUTRAL POSITION SWITCH - STARTER RELAY) 
    1. Check the wire harness between the PNP switch and starter relay.
      1. Disconnect the E25 PNP switch connector.
      2. Remove the starter relay from the engine room No. 1 relay block.
      3. Measure the resistance of the wire harness side connectors.

        Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Specified Condition
      E25-6 (PNP switch) - Relay block starter relay terminal 1 Below 1 Ω
      E25-6 (PNP switch) - Relay block starter relay terminal 1 - Body ground 10 kΩ or higher
    2. Check the wire harness between the starter relay and body ground.
      1. Remove the starter relay from the engine room No. 1 relay block.
      2. Measure the resistance of the wire harness side connector.

        Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Specified Condition
      Relay block starter relay terminal 2 - Body ground Below 1 Ω
    Fig 5: Checking Wire Harness (Park / Neutral Position Switch - Starter Relay)
    G05285743Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 

    OK: Go to next step 

  8. INSPECT ENGINE ROOM RELAY BLOCK (STARTER RELAY VOLTAGE) 
    1. Remove the starter relay from the engine room No. 1 relay block.
    2. Measure the resistance of the wire harness side connector.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Specified Condition
      Relay block starter relay terminal 5 - Body ground 9 to 14 V
    Fig 6: Identifying Starter Relay
    G05285742Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 

    OK: Go to next step 

  9. INSPECT STARTER 

    NG: REPAIR OR REPLACE STARTER 

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

  10. CHECK WIRE HARNESS (ECM - POWER SOURCE CONTROL ECU) 
    1. Disconnect the A6 ECM connector.
    2. Disconnect the K73 ECU connector.
    3. Measure the resistance of the wire harness side connectors.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Specified Condition
      A6-19 (STSW) - K73-39 (STSW) Below 1 Ω
      A6-19 (STSW) or K73-39 (STSW) - Body ground 10 kΩ or higher
    Fig 7: Disconnecting K73 And A6 ECU Connector
    G05285745Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 

    OK: INSPECT STARTING SYSTEM 

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