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Steering Lock does not Lock [08/2015 - ]: Procedure

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

      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) and sent to ID code box (immobiliser code ECU) / OK or NG
      HINT: 
      • The reception state is maintained for 10 seconds.
      • When 10 seconds or more elapse after receiving the signal, the item changes to "NG".
      		 OK: 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.

      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 off and opening a door with the shift lever in P, and OK is displayed on the Techstream screen.

    Result: 

    NG 

    See step  7

    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.
      SMART KEY

      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 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: 

    NG 

    See step  11

    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.
      SMART KEY

      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: 

    NG 

    See step  12

    Result: 

    OK 

    See step  4

  4. CHECK HARNESS AND CONNECTOR (POWER SOURCE TERMINAL) 
    1. Make sure that there is no looseness at the locking part and the connecting part of the connector.
    2. Disconnect the E26 steering lock ECU (steering lock actuator assembly) connector.
    3. Measure the resistance and voltage according to the value(s) in the table below.
      GTY569890Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Condition Specified Condition
      E26-1 (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
      E26-7 (B) - Body ground Always 11 to 14 V
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to Steering Lock ECU (Steering Lock Actuator Assembly))

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  5

  5. CHECK HARNESS AND CONNECTOR (GROUND) 
    1. Disconnect the E26 steering lock ECU (steering lock actuator assembly) connector.
    2. Measure the resistance according to the value(s) in the table below.
      GTY555335Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Condition Specified Condition
      E26-1 (GND) - Body ground Always Below 1 Ω
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to Steering Lock ECU (Steering Lock Actuator Assembly))

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  6

  6. INSPECT STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY) 
    1. Reconnect the E26 steering lock ECU (steering lock actuator assembly) connector.
    2. Turn the engine switch off, make sure that the steering is unlocked and move the shift lever to P.
    3. Check the signal waveform according to the condition(s) in the table below.
      GTY568438Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      STANDARD FREQUENCY

      Item Content
      Tester Connection E26-3 (IGE) - E26-1 (GND)
      Tool Setting 2 V/DIV., 200 ms./DIV.
      Vehicle Condition Steering lock motor not operating → Steering lock motor operating → Steering lock motor not operating
      TEXT IN ILLUSTRATION

      *a Component with harness connected
      (Steering Lock ECU (Steering Lock Actuator Assembly))
      *b Steering lock motor not operating
      *c Steering lock motor 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) with the shift lever in P.
        • To lock the steering, turn the engine switch off with the shift lever in P, and then open a door.

    Result: 

    OK 

    REPLACE STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY) 

    (Refer to DISASSEMBLY [08/2015 - ] )

    Result: 

    NG 

    See step  13

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

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      FL Door Courtesy SW Front door courtesy light switch assembly LH / ON or OFF OFF: Front door LH closed
      ON: Front door LH open      		 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 a related part.

      OK

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

    Result: 

    NG 

    GO TO LIGHTING SYSTEM (DOOR COURTESY LIGHT CIRCUIT) 

    (Refer to Door Courtesy Light Circuit [08/2015 - ] )

    Result: 

    OK 

    See step  8

  8. 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.
      POWER SOURCE CONTROL

      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 whether the shift lever position switch (P) is malfunctioning.

      OK

      ON is displayed on the Techstream.

    Result: 

    NG 

    GO TO SMART KEY SYSTEM (for Start Function) (PROBLEM SYMPTOMS TABLE) 

    (Refer to PROBLEM SYMPTOMS TABLE [08/2015 - ] )

    Result: 

    OK 

    See step  9

  9. 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.
      SMART KEY

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

      OK

      Set is displayed on the Techstream.

    Result: 

    NG 

    REPLACE STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY) 

    (Refer to DISASSEMBLY [08/2015 - ] )

    Result: 

    OK 

    See step  10

  10. READ VALUE USING TECHSTREAM (LOCK REQUEST RECEIVE) 
    1. Replace the certification ECU (smart key ECU assembly) with a new one (Refer to REMOVAL [08/2015 - ] ).
    2. Perform registration procedures (Refer to REGISTRATION [08/2015 - 08/2017] , or refer to REGISTRATION [08/2017 - ] ).
    3. Turn the engine switch on (IG).
    4. Use the Data List to check if the steering lock command is functioning properly.
      SMART KEY

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Lock Request Receive Lock request signal received state / OK or NG OK: Lock request signal received for 10 seconds of any of the doors being opened with shift lever in 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

      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: 

    OK 

    END 

    Result: 

    NG 

    REPLACE ID CODE BOX (IMMOBILISER CODE ECU) 

    (Refer to REMOVAL [08/2015 - ] )

  11. REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) 
    1. Replace the certification ECU (smart key ECU assembly) with a new one (Refer to REMOVAL [08/2015 - ] ).
    2. Perform registration procedures (Refer to REGISTRATION [08/2015 - 08/2017] , or refer to REGISTRATION [08/2017 - ] ).
    3. Use the Data List to check if S code certification is functioning properly again.
      SMART KEY

      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 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: 

    OK 

    END 

    Result: 

    NG 

    REPLACE ID CODE BOX (IMMOBILISER CODE ECU) 

    (Refer to REMOVAL [08/2015 - ] )

  12. 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 [08/2015 - ] ).
    2. Perform registration procedures (Refer to REGISTRATION [08/2015 - 08/2017] , or refer to REGISTRATION [08/2017 - ] ).
    3. Use the Data List to check if L code certification is functioning properly again.
      SMART KEY

      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).

      OK

      OK is displayed on the Techstream.

    Result: 

    OK 

    END 

    Result: 

    NG 

    REPLACE ID CODE BOX (IMMOBILISER CODE ECU) 

    (Refer to REMOVAL [08/2015 - ] )

  13. CHECK HARNESS AND CONNECTOR (STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY) - CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)) 

    See step  5

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  14

  14. INSPECT STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY) 
    1. Reconnect the E26 steering lock ECU (steering lock actuator assembly) connector.
    2. Reconnect the E125 certification ECU (smart key ECU assembly) connector.
    3. Measure the voltage according to the value(s) in the table below.
      GTY561486Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Voltage

      Tester Connection Condition Specified Condition
      E26-3 (IGE) - Body ground Always 11 to 14 V
      TEXT IN ILLUSTRATION

      *a Component with harness connected
      (Steering Lock ECU (Steering Lock Actuator Assembly))

    Result: 

    OK 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) 

    (Refer to REMOVAL [08/2015 - ] )

    Result: 

    NG 

    REPLACE STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY) 

    (Refer to DISASSEMBLY [08/2015 - ] )

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