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Engine does not Start [08/2019 - 08/2022]: Procedure

  1. CHECK ENGINE SWITCH CONDITION 
    1. Get into the vehicle while carrying an electrical key transmitter sub-assembly.
    2. Change the shift state to park (P).
    3. With the brake pedal released, check that pressing the engine switch causes the power source mode to change.

      Result

      Result Proceed to
      Power source mode changes: Off → on (ACC) → on (IG) → off A
      Power source mode does not change to on (ACC) or on (IG) B
      Power source mode changes to on (IG) but not to on (ACC) C
      Power source mode changes to on (ACC) but not to on (IG) D

    Result: 

    B 

    GO TO SMART ACCESS SYSTEM WITH PUSH-BUTTON START (for Start Function) (Power Source Mode does not Change to ON (IG and ACC)). Refer to  Power Source Mode does not Change to ON (IG and ACC) [08/2019 - ]  

    Result: 

    C 

    GO TO SMART ACCESS SYSTEM WITH PUSH-BUTTON START (for Start Function) (Power Source Mode does not Change to ON (ACC)). Refer to  Power Source Mode does not Change to ON (ACC) [08/2019 - ]  

    Result: 

    D 

    GO TO SMART ACCESS SYSTEM WITH PUSH-BUTTON START (for Start Function) (Power Source Mode does not Change to ON (IG)). Refer to  Power Source Mode does not Change to ON (IG) [08/2019 - ]  

    Result: 

    A 

    See step  2

  2. READ VALUE USING TECHSTREAM (STOP LIGHT SWITCH1) 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Body Electrical / Power Source Control / Data List.
    5. Read the Data List according to the display on the Techstream.
      POWER SOURCE CONTROL

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Stop Light Switch1 State of brake pedal/
      OFF or ON      		 OFF: Brake pedal released
      ON: Brake pedal depressed
      • Use this item to determine if the stop light switch assembly is malfunctioning.
      • The engine cannot be started when this item is OFF.
      • If the stop light switch assembly is malfunctioning, the engine can be started by pressing and holding the engine switch for a certain period of time.

      OK

      The Techstream display changes correctly in response to the brake pedal operation.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  23

    Result: 

    OK 

    See step  3

  3. READ VALUE USING TECHSTREAM (SHIFT P SIGNAL) 
    1. Enter the following menus: Body Electrical / Power Source Control / Data List.
    2. Read the Data List according to the display on the Techstream.
      POWER SOURCE CONTROL

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Shift P Signal State of brake pedal/
      ON or OFF      		 ON: Shift state park (P)
      OFF: Shift state not park (P)
      • Use this item to determine if the shift position switch is malfunctioning.
      • The engine cannot be started when this item is OFF.

      OK

      The Techstream display changes correctly in response to the shift state.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  20

    Result: 

    OK 

    See step  4

  4. READ VALUE USING TECHSTREAM (NEUTRAL SWITH CLUTCH SW, SHIFT POSITION P OR N) 
    1. Enter the following menus: Body Electrical / Power Source Control / Data List.
    2. Read the Data List according to the display on the Techstream.
      POWER SOURCE CONTROL

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Neutral SW/ Clutch SW Shift position (P, N)/
      ON or OFF      		 ON: Shift state park (P) or (N)
      OFF: Shift state not park (P) or (N)
      • Use this item to determine whether the park/neutral position switch assembly is malfunctioning.
      • When the engine cannot be started due to a park/neutral position switch assembly malfunction, OFF is displayed.
    3. Enter the following menus: Body Electrical / Starting Control / Data List.
    4. Read the Data List according to the display on the Techstream.
      STARTING CONTROL

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Shift Position P or N Park/Neutral position switch status/
      OFF or ON      		 OFF: Shift state not park (P) or (N)
      ON: Shift state park (P) or (N)      		 When OFF is displayed, the engine will not crank.

      OK

      The Techstream display changes correctly in response to the shift state.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  13

    Result: 

    OK 

    See step  5

  5. READ VALUE USING TECHSTREAM (STARTER REQUEST SIGNAL) 
    1. Read the Data List according to the display on the Techstream.
      POWER SOURCE CONTROL

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Starter Request Signal Engine start request signal status/
      OFF or ON      		 OFF: The engine switch is not pressed
      ON: With the shift state park (P) and the brake pedal depressed, the engine switch is pressed and held
      • When the engine cannot be started due to a start request signal malfunction, OFF is displayed.
      • When the engine switch is pressed, the duration of time that ON is displayed will be extremely short. As such, the engine switch needs to be pressed and held for a certain period of time.
      NOTE:

      Check that the key indicator display is displayed on the multi-information display in the combination meter assembly, and then press the engine switch.

      OK

      The Techstream display changes correctly in response to the engine switch operation.

      Result

      Proceed to
      OK
      NG (w/ Steering Lock System)
      NG (w/o Steering Lock System)

    Result: 

    NG (w/ Steering Lock System) 

    See step  11

    Result: 

    NG (w/o Steering Lock System) 

    See step  12

    Result: 

    OK 

    See step  6

  6. READ VALUE USING TECHSTREAM (STARTER SW) 
    1. Get into the vehicle while carrying an electrical key transmitter sub-assembly.
    2. Shift state park (P).
    3. Enter the following menus: Body Electrical / Starting Control / Data List.
    4. Read the Data List while pressing the engine switch with the brake pedal depressed according to the display on the Techstream.
      STARTING CONTROL

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Starter SW Starter operation request/
      OFF or ON      		 OFF: Starter operation not requested
      ON: Starter operation requested      		 When OFF is displayed, the engine will not crank.

      OK

      The Techstream display changes.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [08/2019 - 08/2021]  , or refer to  REMOVAL [08/2021 - ] 

    Result: 

    OK 

    See step  7

  7. CHECK HARNESS AND CONNECTOR (STARTER RELAY ASSEMBLY (ST RELAY) - POWER SUPPLY) 
    1. Remove the starter relay assembly (ST relay).
      GTY905698Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a No. 1 Engine Room Relay Block
      (Starter Relay Assembly (ST Relay) Installation Terminal)
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      Starter relay assembly (ST relay) installation terminal 5 - Body ground Always 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  8

  8. INSPECT STARTER RELAY ASSEMBLY (ST RELAY) 
    1. Remove the starter relay assembly (ST relay).
    2. Inspect the starter relay assembly (ST relay).

      Refer to ON-VEHICLE INSPECTION [08/2015 - ]

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE STARTER RELAY ASSEMBLY (ST RELAY) 

    Result: 

    OK 

    See step  9

  9. CHECK HARNESS AND CONNECTOR (STARTER RELAY ASSEMBLY (ST RELAY) - STARTER ASSEMBLY) 
    1. Disconnect the E3 starter assembly connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      Starter relay assembly (ST relay) installation terminal 3 - D7-1 Always Below 1 Ω
      Starter relay assembly (ST relay) installation terminal 3 or D7-1 - Other terminals and body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  10

  10. CHECK HARNESS AND CONNECTOR (STARTER ASSEMBLY - POWER SUPPLY) 
    1. Disconnect the starter assembly connector.
      GTY955225Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Starter Assembly)
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      D2-1 - Body ground Always 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE STARTER ASSEMBLY. Refer to  REMOVAL [08/2015 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  11. CHECK STEERING LOCK 
    1. Check that the steering unlocks when the engine switch is turned on (ACC).

      OK

      The steering unlocks.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    GO TO STEERING LOCK SYSTEM (Unable to Unlock Steering Wheel (Engine cannot Start)). Refer to  Unable to Unlock Steering Wheel (Engine cannot Start) [08/2019 - 08/2022] 

    Result: 

    OK 

    See step  12

  12. CHECK SECURITY INDICATOR LIGHT (IMMOBILISER FUNCTION UNSET) 
    1. Get into the vehicle while carrying an electrical key transmitter sub-assembly.
    2. Change the shift state to park (P).
    3. Press the engine switch with the brake pedal released and check that the security indicator light changes from blinking to off at the same time that the power source mode changes to on (ACC).

      OK

      The security indicator light changes from blinking to off at the same time that the power source mode changes to on (ACC).

      HINT: 

      The immobiliser function can be determined to be operating correctly if the security indicator light changes from blinking to off at the same time that the power source mode changes to on (ACC).

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [08/2019 - 08/2021]  , or refer to  REMOVAL [08/2021 - ] 

    Result: 

    NG 

    GO TO ENGINE IMMOBILISER SYSTEM (Immobiliser System does not Operate Properly). Refer to  Immobiliser System does not Operate Properly [08/2019 - ] 

  13. READ VALUE USING TECHSTREAM (NEUTRAL SWITH CLUTCH SW, SHIFT POSITION P OR N) 
    1. Disconnect the C29 and G45 ECM connector.
    2. Enter the following menus: Body Electrical / Power Source Control / Data List.
    3. Read the Data List according to the display on the Techstream.
      POWER SOURCE CONTROL

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Neutral SW/ Clutch SW Shift position (P, N)/
      ON or OFF      		 ON: Shift state park (P) or (N)
      OFF: Shift state not park (P) or (N)
      • Use this item to determine whether the park/neutral position switch assembly is malfunctioning.
      • When the engine cannot be started due to a park/neutral position switch assembly malfunction, OFF is displayed.
    4. Enter the following menus: Body Electrical / Starting Control / Data List.
    5. Read the Data List according to the display on the Techstream.
      STARTING CONTROL

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Shift Position P or N Park/Neutral position switch status/
      OFF or ON      		 OFF: Shift state not park (P) or (N)
      ON: Shift state park (P) or (N)      		 When OFF is displayed, the engine will not crank.

      OK

      The Techstream display changes correctly in response to the shift state.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE ECM. Refer to  REMOVAL [08/2015 - ] 

    Result: 

    NG 

    See step  14

  14. INSPECT PARK/NEUTRAL POSITION SWITCH ASSEMBLY 
    1. Remove the park/neutral position switch assembly.

      Refer to REMOVAL [08/2015 - ]

    2. Inspect the park/neutral position switch assembly.

      Refer to INSPECTION [08/2015 - ]

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE PARK/NEUTRAL POSITION SWITCH ASSEMBLY. Refer to  REMOVAL [08/2015 - ] 

    Result: 

    OK 

    See step  15

  15. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - PARK/NEUTRAL POSITION SWITCH ASSEMBLY) 
    1. Disconnect the G111 certification ECU (smart key ECU assembly) connector.
    2. Disconnect the C33 park/neutral position switch assembly connector.
    3. Remove the starter relay assembly (ST relay).
    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      G111-10 (STAR) - C33-4 (B) Always Below 1 Ω
      G111-12 (STA) - C33-5 (L) Always Below 1 Ω
      G111-10 (STAR) or C33-4 (B) - Other terminals and body ground Always 10 kΩ or higher
      G111-12 (STA) or C33-5 (L) - Other terminals and body ground Always 10 kΩ or higher
    5. Connect the G111 certification ECU (smart key ECU assembly) connector.
    6. Connect the C33 park/neutral position switch assembly connector.
    7. Install the starter relay assembly (ST relay).

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  16

  16. CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) (TERMINAL STAR) 
    1. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      J111-10 (STAR) - Body ground Engine switch pressed and held with brake pedal depressed (starter on) → Approximately 1 second after engine switch released (starter off) 6 V or higher* → 1 V or less
      GTY949590Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Certification ECU (Smart Key ECU Assembly))

      HINT: 

      *: While the engine is cranking, the battery voltage may drop to approximately 6 V.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [08/2019 - 08/2021]  , or refer to  REMOVAL [08/2021 - ] 

    Result: 

    OK 

    See step  17

  17. INSPECT STARTER RELAY ASSEMBLY (ST RELAY) 
    1. Remove the starter relay assembly (ST relay).
    2. Inspect the starter relay assembly (ST relay).

      Refer to ON-VEHICLE INSPECTION [08/2015 - ]

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE STARTER RELAY ASSEMBLY (ST RELAY) 

    Result: 

    OK 

    See step  18

  18. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - STARTER RELAY ASSEMBLY (ST RELAY)) 
    1. Measure the voltage according to the value(s) in the table below.
      GTY905698Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a No. 1 Engine Room Relay Block
      (Starter Relay Assembly (ST Relay) Installation Terminal)

      Standard Voltage

      Tester Connection Condition Specified Condition
      Starter relay assembly (ST relay) installation terminal 1 - Body ground Engine switch pressed and held with brake pedal depressed (starter on) → Approximately 1 second after engine switch released (starter off) 6 V or higher* → 1 V or less

      HINT: 

      *: While the engine is cranking, the battery voltage may drop to approximately 6 V.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  19

  19. CHECK HARNESS AND CONNECTOR (STARTER RELAY ASSEMBLY (ST RELAY) - BODY GROUND) 
    1. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      Starter relay assembly (ST relay) installation terminal 2 - Body ground Always Below 1 Ω
      GTY905698Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a No. 1 Engine Room Relay Block
      (Starter Relay Assembly (ST Relay) Installation Terminal)

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [08/2019 - 08/2021]  , or refer to  REMOVAL [08/2021 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  20. CHECK SHIFT LOCK CONTROL ECU SUB-ASSEMBLY (OUTPUT TO CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)) 
    1. Measure the voltage according to the value(s) in the table below.
      GTY954364Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Certification ECU (Smart Key ECU Assembly))

      Standard Voltage

      Tester Connection Condition Specified Condition
      G111-22 (P) - Other terminals and body ground Shift state park (P) → Shift state not park (P) 9 V or higher → 2.76 V or less

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [08/2019 - 08/2021]  , or refer to  REMOVAL [08/2021 - ] 

    Result: 

    NG 

    See step  21

  21. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - SHIFT LOCK CONTROL ECU SUB-ASSEMBLY) 
    1. Disconnect the G111 certification ECU (smart key ECU assembly) connector.
    2. Disconnect the G32 shift lock control ECU sub-assembly connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      G111-22 (P) - G32-11 (P2) Always Below 1 Ω
      G111-22 (P) or G32-11 (P2) - Other terminals and body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  22

  22. CHECK SHIFT LOCK CONTROL ECU SUB-ASSEMBLY 
    1. Reconnect the certification ECU (smart key ECU assembly) connector.
      GTY954364Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Certification ECU (Smart Key ECU Assembly))
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      G111-22 (P) - Other terminals and body ground Shift state park (P) 9 V or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE SHIFT LOCK CONTROL ECU SUB-ASSEMBLY. Refer to  DISASSEMBLY [08/2015 - ] 

    Result: 

    NG 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [08/2019 - 08/2021]  , or refer to  REMOVAL [08/2021 - ] 

  23. CHECK HARNESS AND CONNECTOR (STOP LIGHT SWITCH ASSEMBLY - POWER SUPPLY AND BODY GROUND) 
    1. Disconnect the stop light switch assembly connector.
      GTY962025Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Stop Light Switch Assembly)
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      A5-1 (B) - Body ground Always 11 to 14 V
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A5-3 (GND) - Body ground Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  24

  24. INSPECT STOP LIGHT SWITCH ASSEMBLY 
    1. Inspect the stop light switch assembly.

      Refer to ON-VEHICLE INSPECTION [08/2015 - ]

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE STOP LIGHT SWITCH ASSEMBLY. Refer to  REMOVAL [08/2015 - ] 

    Result: 

    OK 

    See step  25

  25. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - STOP LIGHT SWITCH ASSEMBLY) 
    1. Disconnect the G111 certification ECU (smart key ECU assembly) connector.
    2. Disconnect the G45 ECM connector.
    3. Disconnect the A7 skid control ECU assembly connector.
    4. Disconnect the G32 shift lock control ECU connector.
    5. Remove the VSC ACC relay.
    6. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      G111-2 (STP1) - A5-2 (L) Always Below 1 Ω
      G111-2 (STP1) or A5-2 (L) - Other terminals and body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [08/2019 - 08/2021]  , or refer to  REMOVAL [08/2021 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

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