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Cranking Holding Function Circuit: Wiring Diagram

Refer to DTC P0617 .

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

    OK : CHECK FOR INTERMITTENT PROBLEMS 

    NG : GO TO NEXT STEP 

  2. READ VALUE OF INTELLIGENT TESTER (STA SIGNAL) 
    1. Connect the intelligent tester to the DLC3.
    2. Turn the engine switch on (IG) and turn the tester ON.
    3. Enter the following menus: DIAGNOSIS / ENHANCED OBD II / ACTIVE TEST / STARTER SIG.
    4. Check the result when the engine switch is turned to on (IG) and START.

      Standard 

      ENGINE SWITCH POSITION

      Engine Switch Position ON (IG) START
      STARTER SIG OFF ON

    OK : Go to step   6 

    NG : GO TO NEXT STEP 

  3. INSPECT ECM (STAR AND STSW VOLTAGE) 
    1. Measure the voltage of the A6 and E7 ECM connectors while cranking the engine.

      Standard voltage 

      ECM TERMINALS VOLTAGE SPECIFICATIONS

      Tester Connection Specified Condition
      STAR (E7-4) - E1 (E7-7)  9 to 14 V 
      STSW (A6-19) - E1 (E7-7)  9 to 14 V 
      Fig 1: Identifying A6 And E7 ECM Connectors
      G04018013Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Result: 

      TERMINAL STAR AND TERMINAL STSW VOLTAGE SPECIFICATIONS

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

    B : REPLACE ECM 

    C : Go to step   10 

    A : GO TO NEXT STEP 

  4. INSPECT ST CUT RELAY 
    1. Remove the ST CUT relay from the engine room No. 2 relay block
    2. Measure the resistance of the ST CUT relay.

      Standard resistance 

      ST CUT RELAY TERMINALS RESISTANCE SPECIFICATIONS

      Tester Connection Specified Condition
      3 - 5  10 kΩ or higher 
      3 - 5  Below 1 Ω (when battery voltage applied to terminals 1 and 2) 

    NG : REPLACE ST CUT RELAY 

    Fig 2: Identifying Relay Test Terminals
    G04044792Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK : GO TO NEXT STEP 

  5. INSPECT PARK/NEUTRAL POSITION SWITCH ASSEMBLY 
    1. Disconnect the park/neutral position (PNP) switch connector.
    2. Measure the resistance between each terminal shown below when the shift lever is moved to each range.

      Standard resistance (2WD) 

      PNP SWITCH TERMINALS RESISTANCE SPECIFICATIONS (2WD)

      Shift Position Tester Connection Specified Condition
      P  4 - 5  Below 1 Ω 
      N  4 - 5  Below 1 Ω 

      Standard resistance (4WD) 

      PNP SWITCH TERMINALS RESISTANCE SPECIFICATIONS (4WD)

      Shift Position Tester Connection Specified Condition
      P  6 - 9  Below 1 Ω 
      N  6 - 9  Below 1 Ω 

    NG : REPLACE PARK/NEUTRAL POSITION SWITCH ASSEMBLY 

    Fig 3: Identifying Park/Neutral Position Switch Connectors (2WD/4WD)
    G04018015Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

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

      Standard resistance 

      STARTER RELAY TERMINALS RESISTANCE SPECIFICATIONS

      Tester Connection Specified Condition
      3 - 5  10 kΩ or higher 
      3 - 5  Below 1 Ω (when battery voltage applied to terminals 1 and 2) 

    NG : REPLACE STARTER RELAY 

    Fig 4: Identifying Relay Test Terminals
    G04061617Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK : GO TO NEXT STEP 

  7. CHECK HARNESS AND CONNECTOR (PARK/NEUTRAL POSITION SWITCH - STARTER RELAY) 
    1. Check the harness and the connectors between the park/neutral position switch and the starter relay.
      1. Disconnect the E77*1, E25*2 position switch connector.

        *1: 2WD

        *2: 4WD

      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 (2WD) (Check for open) 

        PNP SWITCH TERMINALS RESISTANCE SPECIFICATIONS - 2WD (CHECK FOR OPEN)

        Tester Connection Specified Condition
        Park/Neutral position switch (E77-5) - Starter relay (1)  Below 1 Ω 

        Standard resistance (4WD) (Check for open) 

        PNP SWITCH TERMINALS RESISTANCE SPECIFICATIONS - 4WD (CHECK FOR OPEN)

        Tester Connection Specified Condition
        Park/Neutral position switch (E25-6) - Starter relay (1)  Below 1 Ω 

        Standard resistance (2WD) (Check for short) 

        PNP SWITCH TERMINALS RESISTANCE SPECIFICATIONS - 2WD (CHECK FOR SHORT)

        Tester Connection Specified Condition
        Park/Neutral position switch (E77-5) or Starter relay (1) - Body ground  10 kΩ or higher 

        Standard resistance (4WD) (Check for short) 

        PNP SWITCH TERMINALS RESISTANCE SPECIFICATIONS - 4WD (CHECK FOR SHORT)

        Tester Connection Specified Condition
        Park/Neutral position switch (E25-6) or Starter relay (1) - Body ground  10 kΩ or higher 
    2. Check the harness and the connector between the starter relay and the body ground.
      1. Remove the starter relay from the engine room No. 1 relay block.
      2. Measure the resistance of the starter relay and the body ground.

        Standard resistance (Check for open) 

        STARTER RELAY TERMINALS RESISTANCE SPECIFICATIONS (CHECK FOR OPEN)

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

    NG : REPAIR OR REPLACE HARNESS AND CONNECTOR 

    Fig 5: Identifying Park/Neutral Position Switch Connectors (2WD/4WD)
    G04018017Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    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 voltage of the engine room No. 1 relay block and the body ground.

      Standard voltage: 

      STARTER RELAY VOLTAGE SPECIFICATIONS

      Tester Connection Specified Condition
      Starter relay (5) - Body ground 9 to 14 V

    NG : REPAIR OR REPLACE HARNESS AND CONNECTOR 

    Fig 6: Identifying Starter Relay Connectors
    G04018018Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK : GO TO NEXT STEP 

  9. INSPECT STARTER ASSEMBLY 

    NG : REPAIR OR REPLACE STARTER ASSEMBLY 

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

  10. 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 A6 ECM connector.
      3. Measure the resistance of the wire harness side connectors.

        Standard resistance (Check for open) 

        ECM TERMINALS RESISTANCE SPECIFICATIONS (CHECK FOR OPEN)

        Tester Connection Specified Condition
        K73-39 (STSW) - A6-19 (STSW)  Below 1 Ω 

        Standard resistance (Check for short) 

        ECM TERMINALS RESISTANCE SPECIFICATIONS (CHECK FOR SHORT)

        Tester Connection Specified Condition
        K73-39 (STSW) or A6-19 (STSW) - Body ground  10 kΩ or higher 

    NG : REPAIR OR REPLACE HARNESS AND CONNECTOR 

    Fig 7: Identifying A6 ECM Connector
    G04018019Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK : GO TO PUSH BUTTON START SYSTEM 

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