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Steering Lock does not Lock [09/2014 - 01/2023]: Procedure

  1. READ VALUE USING TECHSTREAM (LOCK REQUEST RECEIVE) 
    1. Use the Data List to check if the steering lock command is functioning properly.

      Body Electrical > Smart Access > Data List 

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      Lock Request Receive Reception state of steering lock request signal by certification ECU (smart key ECU assembly) sent to ID code box (immobiliser code ECU)
      HINT: 
      • The reception state is maintained for 10 seconds.
      • When 10 seconds or more have elapsed after receiving the signal, the item changes to "NG".
      		 OK or NG OK: Lock request received within 10 seconds of opening any door with engine switch off and shift lever in P
      NG: Except above      		 If this item does not change to "OK" even though the steering lock conditions are met, the certification ECU (smart key ECU assembly) may be malfunctioning.

      Body Electrical > Smart Access > Data List 

      Tester Display
      Lock Request Receive

      OK

      The certification ECU (smart key ECU assembly) receives a lock request signal within 10 seconds of turning the engine switch from on (IG) to on (ACC) or off and opening a door with the shift lever in P, and OK is displayed on the Techstream screen.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  10

    Result: 

    OK 

    See step  2

  2. READ VALUE USING TECHSTREAM (S CODE CHECK) 
    1. Use the Data List to check if S code certification is functioning properly.

      Body Electrical > Smart Access > Data List 

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      S Code Check Verification result between certification ECU (smart key ECU assembly) and ID code box (immobiliser code ECU) OK or NG OK: Verification result normal
      NG: Verification result abnormal      		 When a malfunction is present:
      • 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).

      Body Electrical > Smart Access > Data List 

      Tester Display
      S Code Check

      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. Use the Data List to check if L code certification is functioning properly.

      Body Electrical > Smart Access > Data List 

      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 a malfunction is present:
      • 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).

      Body Electrical > Smart Access > Data List 

      Tester Display
      L Code Check

      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 (POWER SOURCE TERMINAL) 
    1. Disconnect the O27 steering lock ECU (steering lock actuator assembly) connector.
    2. Measure the resistance and voltage according to the value(s) in the table below.
      GTY505492Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Steering Lock ECU (Steering Lock Actuator Assembly))

      Standard Resistance

      Tester Connection Condition Specified Condition
      O27-1 (GND) - Body ground Always Below 1 Ω
      NOTE:

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

      Standard Voltage

      Tester Connection Condition Specified Condition
      O27-7 (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. INSPECT STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY) 
    1. Reconnect the O27 steering lock ECU (steering lock actuator assembly) connector.
    2. Check the signal waveform according to the condition(s) in the table below.
      GTY504133Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Steering Lock ECU (Steering Lock Actuator Assembly))
      *b Steering Lock Motor not Operating
      *c Steering Lock Motor Operating

      Standard Frequency

      Item Content
      Tester Connection O27-3 (IGE) - O27-1 (GND)
      Tool Setting 2 V/DIV., 200 ms./DIV.
      Vehicle Condition Steering lock motor not operating → Operating → Not operating

      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 lever in P, and then open a door.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY). Refer to  DISASSEMBLY [09/2014 - 03/2019]  , or refer to  DISASSEMBLY [03/2019 - 01/2023] 

    Result: 

    NG 

    See step  6

  6. CHECK HARNESS AND CONNECTOR (STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY) - CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)) 
    1. Make sure that there is no looseness at the locking part and the connecting part of the connectors.
    2. Disconnect the O27 steering lock ECU (steering lock actuator assembly) connector.
    3. Disconnect the O6 certification ECU (smart key ECU assembly) connector.
    4. Check for deformation and corrosion of the connector case and terminals.

      OK

      There is no deformation or corrosion of the connector case or terminals.

    5. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      O27-3 (IGE) - O6-24 (SLR+) Always Below 1 Ω
      O27-3 (IGE) or O6-24 (SLR+) - 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. INSPECT STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY) 
    1. Reconnect the O27 steering lock ECU (steering lock actuator assembly) connector.
    2. Reconnect the O6 certification ECU (smart key ECU assembly) connector.
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      O27-3 (IGE) - Body ground Always 11 to 14 V
      GTY510551Courtesy 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 [09/2014 - ] 

    Result: 

    NG 

    REPLACE STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY). Refer to  DISASSEMBLY [09/2014 - 03/2019]  , or refer to  DISASSEMBLY [03/2019 - 01/2023] 

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

      Refer to DISASSEMBLY [09/2014 - 03/2019] , or refer to DISASSEMBLY [03/2019 - 01/2023]

    2. Perform registration.

      Refer to REGISTRATION [09/2014 - 03/2019] , or refer to REGISTRATION [03/2019 - 09/2020] , or refer to REGISTRATION [09/2020 - 01/2023]

    3. Use the Data List to check if L code certification is functioning properly.

      Body Electrical > Smart Access > Data List 

      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 a malfunction is present:
      • 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).

      Body Electrical > Smart Access > Data List 

      Tester Display
      L Code Check

      OK

      OK is displayed on the Techstream.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    END 

    Result: 

    NG 

    REPLACE ID CODE BOX (IMMOBILISER CODE ECU). Refer to  REMOVAL [09/2014 - ] 

  9. REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) 
    1. Replace the certification ECU (smart key ECU assembly) with a new one.

      Refer to REMOVAL [09/2014 - ]

    2. Perform registration.

      Refer to REGISTRATION [09/2014 - 03/2019] , or refer to REGISTRATION [03/2019 - 09/2020] , or refer to REGISTRATION [09/2020 - 01/2023]

    3. Use the Data List to check if S code certification is functioning properly.

      Body Electrical > Smart Access > Data List 

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      S Code Check Verification result between certification ECU (smart key ECU assembly) and ID code box (immobiliser code ECU) OK or NG OK: Verification result normal
      NG: Verification result abnormal      		 When a malfunction is present:
      • 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).

      Body Electrical > Smart Access > Data List 

      Tester Display
      S Code Check

      OK

      OK is displayed on the Techstream.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    END 

    Result: 

    NG 

    REPLACE ID CODE BOX (IMMOBILISER CODE ECU). Refer to  REMOVAL [09/2014 - ] 

  10. READ VALUE USING TECHSTREAM (FL DOOR COURTESY SW) 
    1. Using the Techstream, check the following main body ECU (multiplex network body ECU) Data List item by opening and closing the driver door to confirm the state of the front door courtesy light switch assembly.

      Body Electrical > Main Body > Data List 

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      FL Door Courtesy SW Front door courtesy light switch assembly LH ON or OFF ON: Front door LH open
      OFF: Front door LH closed      		 If this item does not change according to the actual state of the driver door, there is a malfunction in the door courtesy light switch or related part.

      Body Electrical > Main Body > Data List 

      Tester Display
      FL Door Courtesy SW

      OK

      The Data List item changes in accordance with the opening and closing of the driver door.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    GO TO LIGHTING SYSTEM (FRONT DOOR COURTESY SWITCH CIRCUIT). Refer to  Door Courtesy Switch Circuit [09/2014 - ] 

    Result: 

    OK 

    See step  11

  11. READ VALUE USING TECHSTREAM (SHIFT P SIGNAL) 
    1. Move the shift lever to P.
    2. 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
      Shift P Signal Shift position (P) signal ON or OFF ON: Shift lever in P
      OFF: Shift lever not in P
      • Use this item to determine if the shift position switch is malfunctioning.
      • The engine cannot be started when this item is "OFF".

      Body Electrical > Power Source Control > Data List 

      Tester Display
      Shift P Signal

      OK

      ON is displayed on the Techstream.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    GO TO SMART ACCESS SYSTEM WITH PUSH-BUTTON START (for Start Function) (PROBLEM SYMPTOMS TABLE). Refer to  PROBLEM SYMPTOMS TABLE [09/2014 - ] 

    Result: 

    OK 

    See step  12

  12. READ VALUE USING TECHSTREAM (STEERING LOCK) 
    1. Check that the steering is unlocked.
    2. 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
      Steering Lock State of whether steering lock ECU (steering lock actuator assembly) determined steering is locked Set or Unset Set: Steering locked
      Unset: Steering unlocked      		 If this item displays "Unset", the steering is not locked.

      Body Electrical > Smart Access > Data List 

      Tester Display
      Steering Lock

      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 [09/2014 - 03/2019]  , or refer to  DISASSEMBLY [03/2019 - 01/2023] 

    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 [09/2014 - ]

    2. Perform registration.

      Refer to REGISTRATION [09/2014 - 03/2019] , or refer to REGISTRATION [03/2019 - 09/2020] , or refer to REGISTRATION [09/2020 - 01/2023]

    3. Turn the engine switch on (IG).
    4. Use the Data List to check if the steering lock command is functioning properly.

      Body Electrical > Smart Access > Data List 

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      Lock Request Receive Reception state of steering lock request signal by certification ECU (smart key ECU assembly) sent to ID code box (immobiliser code ECU)
      HINT: 
      • The reception state is maintained for 10 seconds.
      • When 10 seconds or more have elapsed after receiving the signal, the item changes to "NG".
      		 OK or NG OK: Lock request received within 10 seconds of opening any door with engine switch off and shift lever in P
      NG: Except above      		 If this item does not change to "OK" even though the steering lock conditions are met, the certification ECU (smart key ECU assembly) may be malfunctioning.

      Body Electrical > Smart Access > Data List 

      Tester Display
      Lock Request Receive

      OK

      The certification ECU (smart key ECU assembly) receives a lock request signal within 10 seconds of turning the engine switch from on (IG) to on (ACC) or off and opening a door with the shift lever in P, and OK is displayed on the Techstream screen.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    END 

    Result: 

    NG 

    REPLACE ID CODE BOX (IMMOBILISER CODE ECU). Refer to  REMOVAL [09/2014 - ] 

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