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Engine does not Start [10/2022 - ]: 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  10

    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. The certification ECU (smart key ECU assembly) displays "Yes" for the "Key Low Battery" item of the Data List 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 [09/2014 - ] 

    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) [11/2017 - ]  

    Result: 

    C 

    GO TO POWER SOURCE MODE DOES NOT CHANGE TO ON (ACC). Refer to  Power Source Mode does not Change to ON (ACC) [09/2014 - ]  

    Result: 

    D 

    GO TO POWER SOURCE MODE DOES NOT CHANGE TO ON (IG). Refer to  Power Source Mode does not Change to ON (IG) [09/2014 - ]  

    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 whether the park/neutral start switch assembly is malfunctioning.
      • When the engine cannot be started due to a park/neutral start 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
      ON: Shift lever in P      		 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 position.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  22

    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 [10/2022 - ] 

    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 whether the stop light switch is malfunctioning.
      • The engine cannot be started when this item is OFF.
      • If the stop light switch 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 operation.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  20

    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: After approx. 1 second has elapsed, the engine switch is released
      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 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  11

    Result: 

    OK 

    See step  9

  9. 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 [09/2014 - ] 

    Result: 

    NG 

    GO TO IMMOBILISER SYSTEM (PROBLEM SYMPTOMS TABLE). Refer to  PROBLEM SYMPTOMS TABLE [10/2022 - ] 

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

      Refer to INSPECTION [09/2014 - ]

      NOTE:

      Do not wrap the lead wire around 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 [09/2014 - ] 

  11. READ VALUE USING TECHSTREAM (STARTER SW) 
    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 / Starting Control / Data List.
    5. Read the Data List according to the display on the Techstream.
    6. Get into the vehicle while carrying the electrical key transmitter sub-assembly, move the shift lever to P, press the engine switch while depressing the brake pedal and confirm that the Techstream display changes.

      Body Electrical > Starting Control > Data List 

      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 malfunctioning, the engine will not crank.

      Body Electrical > Starting Control > Data List 

      Tester Display
      Starter SW

      OK

      The Techstream display changes.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [09/2014 - ] 

    Result: 

    OK 

    See step  12

  12. INSPECT ST NO. 1 RELAY (STARTER RELAY ASSEMBLY) 
    1. Inspect the ST NO. 1 relay (starter relay assembly).

      for 2UR-GSE: Refer to ON-VEHICLE INSPECTION [11/2017 - ]

      for 2GR-FKS: Refer to ON-VEHICLE INSPECTION [11/2017 - ]

      for 8AR-FTS: Refer to ON-VEHICLE INSPECTION [10/2015 - ]

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE ST RELAY (STARTER RELAY ASSEMBLY) 

    Result: 

    OK 

    See step  13

  13. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - BODY GROUND) 
    1. Disconnect the A13 certification ECU (smart key ECU assembly) connector.
      GTY457444Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Certification ECU (Smart Key ECU Assembly))
    2. Disconnect the A117*1, A106*2, F102*2 or A91*3 ECM connectors.
      1. *1: for 2UR-GSE
      2. *2: for 2GR-FKS
      3. *3: for 8AR-FTS
    3. Move the shift lever to P or N.
    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A13-10 (STAR) - Body ground 20°C (68°F) 107.05 to 116.33 Ω
      A13-12 (STA) - Body ground 20°C (68°F) 106.78 to 115.98 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  16

    Result: 

    OK 

    See step  14

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

      for 2UR-GSE: Refer to REMOVAL [11/2017 - ]

      for 2GR-FKS: Refer to REMOVAL [11/2017 - ]

      for 8AR-FTS: Refer to REMOVAL [10/2015 - ]

    2. Inspect the starter assembly.

      for 2UR-GSE: Refer to INSPECTION [11/2017 - ]

      for 2GR-FKS: Refer to INSPECTION [11/2017 - ]

      for 8AR-FTS: Refer to INSPECTION [10/2015 - ]

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE STARTER ASSEMBLY 

    for 2UR-GSE: Refer to REMOVAL [11/2017 - ]

    for 2GR-FKS: Refer to REMOVAL [11/2017 - ]

    for 8AR-FTS: Refer to REMOVAL [10/2015 - ]

    Result: 

    OK 

    See step  15

  15. CHECK HARNESS AND CONNECTOR (BATTERY - STARTER ASSEMBLY AND ST NO. 1 RELAY (STARTER RELAY ASSEMBLY) 
    1. Disconnect the F192*1 or F85*2 and G2*1 or G4*2 starter assembly connectors.
      1. *1: for 2UR-GSE and 2GR-FKS
      2. *2: for 8AR-FTS
    2. Remove the ST NO. 1 relay (starter relay assembly) from the No. 1 engine room relay block and No. 1 junction block assembly.
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      FOR 2UR-GSE AND 2GR-FKS

      Tester Connection Condition Specified Condition
      G2-1 (B) - Body ground Always 11 to 14 V
      5 (ST NO. 1 relay (starter relay assembly)) - Body ground Always 11 to 14 V
      FOR 8AR-FTS

      Tester Connection Condition Specified Condition
      G4-1 (B) - Body ground Always 11 to 14 V
      5 (ST NO. 1 relay (starter relay assembly)) - Body ground Always 11 to 14 V
    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      FOR 2UR-GSE AND 2GR-FKS

      Tester Connection Condition Specified Condition
      3 (ST NO. 1 relay (starter relay assembly)) - F192-1 (ST) Always Below 1 Ω
      3 (ST NO. 1 relay (starter relay assembly)) or F192-1 (ST) - Body ground Always 10 kΩ or higher
      FOR 8AR-FTS

      Tester Connection Condition Specified Condition
      3 (ST NO. 1 relay (starter relay assembly)) - F85-1 (ST) Always Below 1 Ω
      3 (ST NO. 1 relay (starter relay assembly)) or F85-1 (ST) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [10/2022 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  16. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - PARK/NEUTRAL POSITION SWITCH) 
    1. Disconnect the A13 certification ECU (smart key ECU assembly) connector.
    2. Disconnect the F176*1 or F54*2 park/neutral position switch assembly connector.
      1. *1: for 2UR-GSE
      2. *2: except 2UR-GSE
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      FOR 2UR-GSE

      Tester Connection Condition Specified Condition
      A13-10 (STAR) - F176-4 (B) Always Below 1 Ω
      A13-10 (STAR) or F176-4 (B) - Body ground Always 10 kΩ or higher
      EXCEPT 2UR-GSE

      Tester Connection Condition Specified Condition
      A13-10 (STAR) - F54-4 (B) Always Below 1 Ω
      A13-10 (STAR) or F54-4 (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  17

  17. CHECK HARNESS AND CONNECTOR (PARK/NEUTRAL POSITION SWITCH - ST NO. 1 RELAY (STARTER RELAY ASSEMBLY) 
    1. Disconnect the F176*1 or F54*2 park/neutral position switch assembly connector.
      1. *1: for 2UR-GSE
      2. *2: except 2UR-GSE
    2. Remove the ST NO. 1 relay (starter relay assembly) from the No. 1 engine room relay block and No. 1 junction block assembly.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      FOR 2UR-GSE

      Tester Connection Condition Specified Condition
      F176-5 (L) - 2 (ST NO. 1 relay (starter relay assembly)) Always Below 1 Ω
      F176-5 (L) or 2 (ST NO. 1 relay (starter relay assembly)) - Body ground Always 10 kΩ or higher
      EXCEPT 2UR-GSE

      Tester Connection Condition Specified Condition
      F54-5 (L) - 2 (ST NO. 1 relay (starter relay assembly)) Always Below 1 Ω
      F54-5 (L) or 2 (ST NO. 1 relay (starter relay assembly)) - 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 (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - ST NO. 1 RELAY (STARTER RELAY ASSEMBLY) 
    1. Disconnect the A13 certification ECU (smart key ECU assembly) connector.
    2. Remove the ST NO. 1 relay (starter relay assembly) from the No. 1 engine room relay block and No. 1 junction block assembly.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A13-12 (STA) - 2 (ST NO. 1 relay (starter relay assembly)) Always Below 1 Ω
      A13-12 (STA) or 2 (ST NO. 1 relay (starter relay assembly)) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  19

  19. CHECK HARNESS AND CONNECTOR (ST NO. 1 RELAY (STARTER RELAY ASSEMBLY - BODY GROUND) 
    1. Remove the ST NO. 1 relay (starter relay assembly) from the No. 1 engine room relay block and No. 1 junction block assembly.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      1 (ST NO. 1 relay (starter relay assembly)) - Body ground Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [10/2022 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  20. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - STOP LIGHT SWITCH ASSEMBLY) 
    1. Disconnect the A13 certification ECU (smart key ECU assembly) connector.
    2. Disconnect the A56 stop light switch assembly connector.
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      A56-1 (B) - Body ground Always 11 to 14 V
      GTY466966Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Stop Light Switch Assembly)
    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A13-2 (STP1) - A56-2 (L) Always Below 1 Ω
      A13-2 (STP1) or A56-2 (L) - Body ground Always 10 kΩ or higher
      A56-3 (GND) - Body ground Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  21

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

      Refer to ON-VEHICLE INSPECTION [09/2014 - ]

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [09/2014 - ] 

    Result: 

    NG 

    REPLACE STOP LIGHT SWITCH ASSEMBLY. Refer to  REMOVAL [09/2014 - ] 

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

      for A760H: Refer to REMOVAL [09/2014 - ]

      for AA80E: Refer to REMOVAL [09/2014 - ]

      for AA81E: Refer to REMOVAL [09/2014 - ]

    2. Inspect the park/neutral position switch assembly.

      for A760H: Refer to INSPECTION [09/2014 - ]

      for AA80E: Refer to INSPECTION [09/2014 - ]

      for AA81E: Refer to INSPECTION [09/2014 - ]

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE PARK/NEUTRAL POSITION SWITCH ASSEMBLY 

    for A760H: Refer to REMOVAL [09/2014 - ]

    for AA80E: Refer to REMOVAL [09/2014 - ]

    for AA81E: Refer to REMOVAL [09/2014 - ]

    Result: 

    OK 

    See step  23

  23. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - PARK/NEUTRAL POSITION SWITCH) 
    1. Disconnect the A13 certification ECU (smart key ECU assembly) connector.
    2. Disconnect the F176*1 or F54*2 park/neutral position switch assembly connector.
      1. *1: for 2UR-GSE
      2. *2: except 2UR-GSE
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      FOR 2UR-GSE

      Tester Connection Condition Specified Condition
      A13-10 (STAR) - F176-4 (B) Always Below 1 Ω
      A13-10 (STAR) or F176-4 (B) - Body ground Always 10 kΩ or higher
      EXCEPT 2UR-GSE

      Tester Connection Condition Specified Condition
      A13-10 (STAR) - F54-4 (B) Always Below 1 Ω
      A13-10 (STAR) or F54-4 (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 [09/2014 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

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