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Steering Lock does not Lock [08/2019 - 08/2022]: Procedure

  1. READ VALUE USING TECHSTREAM (LOCK REQUEST RECEIVE) 
    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.
      SMART ACCESS

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Lock Request Receive Status of steering lock command from certification ECU (smart key ECU assembly)/
      OK or NG      		 OK: Lock request signal received within 10 seconds of any of the doors being opened with shift state park (P) and engine switch off.
      NG: Except above      		 If OK is not displayed even though the steering lock conditions are met, the certification ECU (smart key ECU assembly) may be malfunctioning.

      OK

      Within 10 seconds of any of the doors being opened with shift state park (P) and engine switch off, the Data List item changes to "OK".

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  10

    Result: 

    OK 

    See step  2

  2. READ VALUE USING TECHSTREAM (S CODE CHECK) 
    1. Enter the following menus: Body Electrical / Smart Access / Data List.
    2. Read the Data List according to the display on the Techstream.
      SMART ACCESS

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      S Code Check S code verification result
      OK or NG      		 OK: Verification result normal
      NG: Verification result abnormal      		 When NG is displayed:
      • The ID code for the certification ECU (smart key ECU assembly) or ID code box (immobiliser code ECU) is not registered, or the certification ECU (smart key ECU assembly) or ID code box (immobiliser code ECU) is malfunctioning.
      • The steering cannot be locked.
      • The steering cannot be unlocked (the engine cannot be started).

      OK

      OK is displayed on the Techstream.

      HINT: 

      Reasons for verification failure:

      • The certification ECU (smart key ECU assembly) or ID code box (immobiliser code ECU) is malfunctioning.
      • There is a problem with the communication between ECUs.
      • An ECU is replaced, but is not registered.
      • An ECU is replaced with an ECU which has a code already stored in it.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  9

    Result: 

    OK 

    See step  3

  3. READ VALUE USING TECHSTREAM (L CODE CHECK) 
    1. Enter the following menus: Body Electrical / Smart Access / Data List.
    2. Read the Data List according to the display on the Techstream.
      SMART ACCESS

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      L Code Check Verification result between ID code box (immobiliser code ECU) and steering lock ECU (steering lock actuator assembly)/
      OK or NG      		 OK: Verification result normal
      NG: Verification result abnormal      		 When NG is displayed:
      • The ID code for the ID code box (immobiliser code ECU) or steering lock ECU (steering lock actuator assembly) is not registered, or the ID code box (immobiliser code ECU) or steering lock ECU (steering lock actuator assembly) is malfunctioning.
      • The steering cannot be locked.
      • The steering cannot be unlocked (the engine cannot be started).

      OK

      OK is displayed on the Techstream.

      HINT: 

      Reasons for verification failure:

      • The steering lock ECU (steering lock actuator assembly) or ID code box (immobiliser code ECU) is malfunctioning.
      • There is a problem with the communication between ECUs.
      • An ECU is replaced, but is not registered.
      • An ECU is replaced with an ECU which has a code already stored in it.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  8

    Result: 

    OK 

    See step  4

  4. CHECK HARNESS AND CONNECTOR (STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY) - POWER SUPPLY AND BODY GROUND) 
    1. Disconnect the steering lock ECU (steering lock actuator assembly) connector.
      GTY954715Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Steering Lock ECU (Steering Lock Actuator Assembly))
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      G23-1 (GND) - Body ground Always Below 1 Ω
      NOTE:

      If the result is not as specified, check for looseness in the ground cable connection.

    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      G23-7 (B) - Body ground Always 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  5

  5. CHECK STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY) (MOTOR ACTIVATION COMMAND SIGNAL) 
    1. Reconnect the steering lock ECU (steering lock actuator assembly) connector.
    2. Using an oscilloscope, check the waveform.
      GTY955429Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Steering Lock ECU (Steering Lock Actuator Assembly))
      *b Waveform
      *c Steering lock motor not operating
      *d Steering lock motor operating

      OK

      Tester Connection Tool Setting Condition Specified Condition
      G23-3 (IGE) - G23-1 (GND) 2 V/DIV., 200 ms./DIV. Any door opened when following conditions are met, and then steering lock motor activated:
      • Shift state park (P)
      • Steering lock unlocked in advance by carrying key and turning engine switch on (IG)
      • After above conditions are met, engine switch turned off
      		 Pulse generation
      (See waveform)

      HINT: 

      • When taking measurements when the lock motor is stopped, it is not necessary to perform any operations.
      • In order to take measurements when the lock motor is operating, perform either of the following operations:
        • To unlock the steering, carry the key and turn the engine switch on (ACC) or on (IG).
        • To lock the steering, turn the engine switch off with the shift state park (P), and then open a door.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY). Refer to  DISASSEMBLY [08/2019 - 08/2022] 

    Result: 

    NG 

    See step  6

  6. CHECK HARNESS AND CONNECTOR (STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY) - CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)) 
    1. Disconnect the G23 steering lock ECU (steering lock actuator assembly) connector.
    2. Disconnect the G113 certification ECU (smart key ECU assembly) connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      G23-3 (IGE) - G113-24 (SLR+) Always Below 1 Ω
      G23-3 (IGE) or G113-24 (SLR+) - 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  7

  7. CHECK STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY) 
    1. Reconnect the steering lock ECU (steering lock actuator assembly) connector.
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      G23-3 (IGE) - Body ground Always 11 to 14 V
      GTY955632Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Steering Lock ECU (Steering Lock Actuator Assembly))

      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 

    REPLACE STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY). Refer to  DISASSEMBLY [08/2019 - 08/2022] 

  8. CHECK STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY) 
    1. Replace the steering lock ECU (steering lock actuator assembly) with a new one.

      Refer to DISASSEMBLY [08/2019 - 08/2022]

    2. Enter the following menus: Body Electrical / Smart Access / Data List.
    3. Read the Data List according to the display on the Techstream.
      SMART ACCESS

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      L Code Check Verification result between ID code box (immobiliser code ECU) and steering lock ECU (steering lock actuator assembly)/
      OK or NG      		 OK: Verification result normal
      NG: Verification result abnormal      		 When NG is displayed:
      • The ID code for the ID code box (immobiliser code ECU) or steering lock ECU (steering lock actuator assembly) is not registered, or the ID code box (immobiliser code ECU) or steering lock ECU (steering lock actuator assembly) is malfunctioning.
      • The steering cannot be locked.
      • The steering cannot be unlocked (the engine cannot be started).

      OK

      OK is displayed on the Techstream.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    END (STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY) WAS DEFECTIVE) 

    Result: 

    NG 

    REPLACE ID CODE BOX (IMMOBILISER CODE ECU). Refer to  REMOVAL [08/2015 - ] 

  9. CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) 
    1. Replace the certification ECU (smart key ECU assembly) with a new one and perform registration again.

      Refer to REMOVAL [08/2019 - 08/2021] , or refer to REMOVAL [08/2021 - ]

      HINT: 

      Refer to Registration.

      Refer to REGISTRATION [08/2019 - 08/2021] , or refer to REGISTRATION [08/2021 - 08/2022]

    2. Enter the following menus: Body Electrical / Smart Access / Data List.
    3. Read the Data List according to the display on the Techstream.
      SMART ACCESS

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      S Code Check S code verification result/
      OK or NG      		 OK: Verification result normal
      NG: Verification result abnormal      		 When NG is displayed:
      • The ID code for the certification ECU (smart key ECU assembly) or ID code box (immobiliser code ECU) is not registered, or the certification ECU (smart key ECU assembly) or ID code box (immobiliser code ECU) is malfunctioning.
      • The steering cannot be locked.
      • The steering cannot be unlocked (the engine cannot be started).

      OK

      OK is displayed on the Techstream.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    END (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) WAS DEFECTIVE) 

    Result: 

    NG 

    REPLACE ID CODE BOX (IMMOBILISER CODE ECU). Refer to  REMOVAL [08/2015 - ] 

  10. READ VALUE USING TECHSTREAM (DOOR COURTESY SW) 
    1. Enter the following menus: Body Electrical / Main Body / Data List.
    2. Read the Data List according to the display on the Techstream.
      MAIN BODY

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      RR Door Courtesy SW Rear door RH courtesy light switch
      ON or OFF      		 ON: Rear door RH open
      OFF: Rear door RH closed      		 -
      RL Door Courtesy SW Rear door LH courtesy light switch
      ON or OFF      		 ON: Rear door LH open
      OFF: Rear door LH closed      		 -
      FR Door Courtesy SW Front door courtesy light switch assembly RH signal
      OFF or ON      		 OFF: Front door RH closed
      ON: Front door RH open      		 -
      FL Door Courtesy SW Front door courtesy light switch assembly LH signal
      OFF or ON      		 OFF: Front door LH closed
      ON: Front door LH open      		 -

      OK

      The Data List item changes in accordance with the opening and closing of all the doors.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    GO TO LIGHTING SYSTEM (DOOR COURTESY SWITCH CIRCUIT). Refer to  Door Courtesy Switch Circuit [08/2019 - ] 

    Result: 

    OK 

    See step  11

  11. READ VALUE USING TECHSTREAM (SHIFT P SIGNAL) 
    1. Move the shift state park (P).
    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
      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

      ON is displayed on the Techstream.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  14

    Result: 

    OK 

    See step  12

  12. READ VALUE USING TECHSTREAM (STEERING LOCK) 
    1. Check that the steering is unlocked.
    2. Enter the following menus: Body Electrical / Smart Access / Data List.
    3. Read the Data List according to the display on the Techstream.
      SMART ACCESS

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Steering Lock Steering lock ECU (steering lock actuator assembly) lock confirmation status/
      Unset or Set      		 Unset: Lock not confirmed
      Set: Lock confirmed      		 When Unset is displayed, the steering is not locked.

      OK

      Set is displayed on the Techstream.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY). Refer to  DISASSEMBLY [08/2019 - 08/2022] 

    Result: 

    OK 

    See step  13

  13. READ VALUE USING TECHSTREAM (LOCK REQUEST RECEIVE) 
    1. Replace the certification ECU (smart key ECU assembly) with a new one.

      Refer to REMOVAL [08/2019 - 08/2021] , or refer to REMOVAL [08/2021 - ]

    2. Perform registration.

      Refer to REGISTRATION [08/2019 - 08/2021] , or refer to REGISTRATION [08/2021 - 08/2022]

      HINT: 

      Refer to Registration.

    3. Enter the following menus: Body Electrical / Smart Access / Data List.
    4. Read the Data List according to the display on the Techstream.
      SMART ACCESS

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Lock Request Receive Status of steering unlock command from certification ECU (smart key ECU assembly)/
      OK or NG      		 OK: Lock request signal received within 10 seconds of any of the doors being opened with shift state park (P) and engine switch off.
      NG: Except above
      • The engine cannot be started when an unlock request signal cannot be received.
      • If OK is not displayed even though the steering unlock conditions are met, the certification ECU (smart key ECU assembly) may be malfunctioning.

      OK

      Within 10 seconds of any of the doors being opened with shift state park (P) and engine switch off, the Data List item changes to "OK".

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    END (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) WAS DEFECTIVE) 

    Result: 

    NG 

    REPLACE ID CODE BOX (IMMOBILISER CODE ECU). Refer to  REMOVAL [08/2015 - ] 

  14. 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.
      GTY954365Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Certification ECU (Smart Key ECU Assembly))

      Standard Voltage

      Tester Connection Condition Specified Condition
      G113-22 (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  15

  15. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - SHIFT LOCK CONTROL ECU SUB-ASSEMBLY) 
    1. Disconnect the G113 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
      G113-22 (P) - G32-11 (P2) Always Below 1 Ω
      G113-22 (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  16

  16. CHECK SHIFT LOCK CONTROL ECU SUB-ASSEMBLY 
    1. Reconnect the certification ECU (smart key ECU assembly) connector.
      GTY954365Courtesy 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
      G113-22 (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 - ] 

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