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Engine does not Start [09/2015 - ]: Procedure

  1. CHECK ELECTRICAL KEY TRANSMITTER SUB-ASSEMBLY 
    1. Press a switch of the electrical key transmitter sub-assembly.

      OK

      The electrical key transmitter sub-assembly LED illuminates.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  19

    Result: 

    OK 

    See step  2

  2. READ VALUE USING TECHSTREAM (KEY LOW BATTERY) 
    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 / Smart Access / Data List.
    5. Read the Data List according to the display on the Techstream.

      Body Electrical > Smart Access > Data List 

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      Key Low Battery Transmitter battery depleted No or Yes No: Transmitter battery not depleted
      Yes: Transmitter battery depleted      		 The electrical key transmitter sub-assembly sends voltage information to the certification ECU (smart key ECU assembly) when it is transmitting. "Yes" is displayed for the Data List item "Key Low Battery" when this voltage information indicates 2.2 V or less. This Data List item should be checked when the electrical key transmitter sub-assembly is at room temperature (example: at -20°C (-4°F), "Yes" may be displayed even if the transmitter battery is new).

      Body Electrical > Smart Access > Data List 

      Tester Display
      Key Low Battery

      Result

      Result Proceed to
      "No" is displayed on the Techstream screen A
      "Yes" is displayed on the Techstream screen B

    Result: 

    B 

    REPLACE TRANSMITTER BATTERY. Refer to  REPLACEMENT [09/2015 - ] 

    Result: 

    A 

    See step  3

  3. CHECK WAVE ENVIRONMENT 
    1. If the problem occurs in certain locations or times of day, the possibility of wave interference is high.

      HINT: 

      Whether the problem is due to wave interference can be checked by holding the electrical key transmitter sub-assembly near the door control receiver.

      OK

      Engine starts.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    AFFECTED BY WAVE INTERFERENCE 

    Result: 

    NG 

    See step  4

  4. CHECK ENGINE SWITCH CONDITION 
    1. Get into the vehicle while carrying an electrical key transmitter sub-assembly.
    2. Move the shift lever to 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 POWER SOURCE MODE DOES NOT CHANGE TO ON (IG AND ACC). Refer to  Power Source Mode does not Change to ON (IG and ACC) [09/2015 - 12/2017]  , or refer to  Power Source Mode does not Change to ON (IG and ACC) [12/2017 - ]  

    Result: 

    C 

    GO TO POWER SOURCE MODE DOES NOT CHANGE TO ON (ACC). Refer to  Power Source Mode does not Change to ON (ACC) [09/2015 - ]  

    Result: 

    D 

    GO TO POWER SOURCE MODE DOES NOT CHANGE TO ON (IG). Refer to  Power Source Mode does not Change to ON (IG) [09/2015 - ]  

    Result: 

    A 

    See step  5

  5. READ VALUE USING TECHSTREAM (NEUTRAL SW/ CLUTCH SW, SHIFT POSITION P OR N) 
    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 or Starting Control / Data List.
    5. Read the Data List according to the display on the Techstream.

      Body Electrical > Power Source Control > Data List 

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      Neutral SW/ Clutch SW Shift position (P and N) OFF or ON OFF: Shift lever in any position other than P or N
      ON: Shift lever in P or N
      • Use this item to determine if 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.

      Body Electrical > Power Source Control > Data List 

      Tester Display
      Neutral SW/ Clutch SW

      Body Electrical > Starting Control > Data List 

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      Shift Position P or N Park/Neutral position switch status OFF or ON OFF: Shift lever not in P or N
      ON: Shift lever in P or N      		 When malfunctioning, the engine will not crank.

      Body Electrical > Starting Control > Data List 

      Tester Display
      Shift Position P or N

      OK

      The Techstream display changes correctly in response to the shift lever operation.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  25

    Result: 

    OK 

    See step  6

  6. CHECK FOR DTC 
    1. Using the Techstream, check for certification ECU (smart key ECU assembly) DTCs.

      Body Electrical > Smart Access > Trouble Codes 

      Body Electrical > Power Source Control > Trouble Codes 

      Body Electrical > Starting Control > Trouble Codes 

      Result

      Result Proceed to
      DTCs are not output A
      Smart access system with push-button start (for Start Function) DTCs are output B

    Result: 

    B 

    GO TO DIAGNOSTIC TROUBLE CODE CHART. Refer to  DIAGNOSTIC TROUBLE CODE CHART [09/2015 - 08/2019]  , or refer to  DIAGNOSTIC TROUBLE CODE CHART [08/2019 - ] 

    Result: 

    A 

    See step  7

  7. 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.

      Body Electrical > Power Source Control > Data List 

      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.

      Body Electrical > Power Source Control > Data List 

      Tester Display
      Stop Light Switch1

      OK

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

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  22

    Result: 

    OK 

    See step  8

  8. READ VALUE USING TECHSTREAM (STARTER REQUEST 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: Body Electrical / Power Source Control / Data List.
    5. Read the Data List according to the display on the Techstream.

      Body Electrical > Power Source Control > Data List 

      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 lever in 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.

      Body Electrical > Power Source Control > Data List 

      Tester Display
      Starter Request Signal
      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

    Result: 

    NG 

    See step  20

    Result: 

    OK 

    See step  9

  9. INSPECT ST RELAY 
    1. Inspect the ST relay.

      Refer to ON-VEHICLE INSPECTION [09/2015 - ]

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE ST RELAY (STARTER RELAY ASSEMBLY) 

    Result: 

    OK 

    See step  10

  10. INSPECT STARTER ASSEMBLY 
    1. Remove the starter assembly.

      Refer to REMOVAL [09/2015 - 08/2016] , or refer to REMOVAL [08/2016 - 08/2019] , or refer to REMOVAL [08/2019 - ]

    2. Inspect the starter assembly.

      Refer to INSPECTION [09/2015 - 08/2019] , or refer to INSPECTION [08/2019 - ]

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE STARTER ASSEMBLY. Refer to  REMOVAL [09/2015 - 08/2016]  , or refer to  REMOVAL [08/2016 - 08/2019]  , or refer to  REMOVAL [08/2019 - ] 

    Result: 

    OK 

    See step  11

  11. CHECK HARNESS AND CONNECTOR (BATTERY - STARTER ASSEMBLY AND ST RELAY) 
    1. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      D71-1 (B) - Body ground Always 11 to 14 V
      5 (ST relay) - Body ground Always 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  12

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

      Standard Resistance

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

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  13

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

      Standard Resistance

      Tester Connection Condition Specified Condition
      3 (ST relay) - D21-1 (ST) Always Below 1 Ω
      3 (ST relay) or D21-1 (ST) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  14

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

      Standard Voltage

      Tester Connection Condition Specified Condition
      A74-20 (STA) - 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* → 1.0 V or less
      GTY651013Courtesy 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 [09/2015 - 08/2016]  , or refer to  REMOVAL [08/2016 - 08/2019]  , or refer to  REMOVAL [08/2019 - ] 

    Result: 

    OK 

    See step  15

  15. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - ST RELAY) 
    1. Disconnect the A74 certification ECU (smart key ECU assembly) connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A74-20 (STA) - 2 (ST relay) Always Below 1 Ω
      A74-20 (STA) or 2 (ST relay) - Body ground Always 10 kΩ or higher

      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) 
    1. Reconnect the A74 certification ECU (smart key ECU assembly) connector.
      GTY651009Courtesy 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
      A74-9 (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* → 1.0 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 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [09/2015 - 08/2016]  , or refer to  REMOVAL [08/2016 - 08/2019]  , or refer to  REMOVAL [08/2019 - ] 

    Result: 

    OK 

    See step  17

  17. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - PARK/NEUTRAL POSITION SWITCH ASSEMBLY) 
    1. Disconnect the A74 certification ECU (smart key ECU assembly) connector.
    2. Disconnect the D15 park/neutral position switch assembly connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A74-9 (STAR) - D15-4 (B) Always Below 1 Ω
      A74-9 (STAR) or D15-4 (B) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  18

  18. CHECK HARNESS AND CONNECTOR (PARK/NEUTRAL POSITION SWITCH ASSEMBLY - ST RELAY (STARTER RELAY ASSEMBLY) 
    1. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      D15-9 (L) - 2 (ST relay) Always Below 1 Ω
      D15-9 (L) or 2 (ST relay) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    GO TO SFI SYSTEM. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [09/2015 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  19. INSPECT TRANSMITTER BATTERY 
    1. Inspect the transmitter battery.

      Refer to INSPECTION [09/2015 - ]

      NOTE:

      Do not wrap the lead wire ground a terminal, wedge it between terminals, or solder it. The terminal may be deformed or damaged, and the transmitter battery will not be able to be installed correctly.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE ELECTRICAL KEY TRANSMITTER SUB-ASSEMBLY 

    Result: 

    NG 

    REPLACE TRANSMITTER BATTERY. Refer to  REPLACEMENT [09/2015 - ] 

  20. 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). Refer to  Unable to Unlock Steering Wheel (Engine cannot Start) [09/2015 - ] 

    Result: 

    OK 

    See step  21

  21. CHECK SECURITY INDICATOR LIGHT (IMMOBILISER SYSTEM UNSET) 
    1. Get into the vehicle while carrying an electrical key transmitter sub-assembly.
    2. Move the shift lever to 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).

      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).

      OK

      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 [09/2015 - 08/2016]  , or refer to  REMOVAL [08/2016 - 08/2019]  , or refer to  REMOVAL [08/2019 - ] 

    Result: 

    NG 

    GO TO IMMOBILISER SYSTEM (PROBLEM SYMPTOMS TABLE). Refer to  PROBLEM SYMPTOMS TABLE [09/2015 - ] 

  22. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - POWER SUPPLY AND BODY GROUND) 
    1. Disconnect the A55 stop light switch assembly connector.
      GTY667976Courtesy 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
      A55-1 (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
      A55-3 (GND) - Body ground Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  23

  23. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - STOP LIGHT SWITCH ASSEMBLY) 
    1. Disconnect the R1 certification ECU (smart key ECU assembly) connector.
    2. Disconnect the A37 ECM connector.
    3. Disconnect the A41 skid control ECU (brake actuator assembly) connector.
    4. Disconnect the J22 transmission floor shift assembly connector.
    5. Disconnect the 1D semiconductor pwr integration ECU connector.
    6. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      R1-25 (STP1) - A55-2 (L) Always Below 1 Ω
      R1-25 (STP1) or A55-2 (L) - Body ground Always 10 kΩ or higher

      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 [09/2015 - ]

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [09/2015 - 08/2016]  , or refer to  REMOVAL [08/2016 - 08/2019]  , or refer to  REMOVAL [08/2019 - ] 

    Result: 

    NG 

    REPLACE STOP LIGHT SWITCH ASSEMBLY. Refer to  REMOVAL [09/2015 - 08/2016]  , or refer to  REMOVAL [08/2016 - 08/2019]  , or refer to  REMOVAL [08/2019 - ] 

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

      Refer to REMOVAL [09/2015 - 08/2016] , or refer to REMOVAL [08/2016 - 08/2019] , or refer to REMOVAL [08/2019 - ]

    2. Inspect the park/neutral position switch assembly.

      Refer to INSPECTION [09/2015 - ]

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE PARK/NEUTRAL POSITION SWITCH ASSEMBLY. Refer to  REMOVAL [09/2015 - 08/2016]  , or refer to  REMOVAL [08/2016 - 08/2019]  , or refer to  REMOVAL [08/2019 - ] 

    Result: 

    OK 

    See step  26

  26. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - PARK/NEUTRAL POSITION SWITCH ASSEMBLY) 
    1. Disconnect the A74 certification ECU (smart key ECU assembly) connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A74-9 (STAR) - D15-4 (B) Always Below 1 Ω
      A74-9 (STAR) or D15-4 (B) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [09/2015 - 08/2016]  , or refer to  REMOVAL [08/2016 - 08/2019]  , or refer to  REMOVAL [08/2019 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

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