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Steering Lock does not Lock [08/2019 - ]: 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 Key / Data List.
    5. Read the Data List according to the display on the Techstream.
      SMART KEY

      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  8

    Result: 

    OK 

    See step  2

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

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      L Code Check Verification result between certification ECU (smart key ECU assembly) and steering lock ECU (upper steering column with switch bracket assembly)/
      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 steering lock ECU (upper steering column with switch bracket assembly) is not registered, or the certification ECU (smart key ECU assembly) or steering lock ECU (upper steering column with switch bracket 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 (upper steering column with switch bracket assembly) or certification ECU (smart key ECU assembly) 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  5

    Result: 

    OK 

    See step  3

  3. CHECK HARNESS AND CONNECTOR (STEERING LOCK ECU (UPPER STEERING COLUMN WITH SWITCH BRACKET ASSEMBLY) - POWER SUPPLY AND BODY GROUND) 
    1. Disconnect the steering lock ECU (upper steering column with switch bracket assembly) connector.
      GTY931087Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Steering Lock ECU (Upper Steering Column with Switch Bracket Assembly))
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      H196-1 (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
      H196-7 (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  4

  4. CHECK STEERING LOCK ECU (UPPER STEERING COLUMN WITH SWITCH BRACKET ASSEMBLY) (MOTOR ACTIVATION COMMAND SIGNAL) 
    1. Reconnect the steering lock ECU (upper steering column with switch bracket assembly) connector.
    2. Using an oscilloscope, check the waveform.
      GTY858103Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Steering Lock ECU (Upper Steering Column with Switch Bracket Assembly))
      *b Waveform
      *c Steering Lock Motor not Operating
      *d Steering Lock Motor Operating

      OK

      Tester Connection Tool Setting Condition Specified Condition
      H196-3 (IGE) - H196-1 (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 (UPPER STEERING COLUMN WITH SWITCH BRACKET ASSEMBLY) 

    for Power Tilt and Power Telescopic Steering Column:

    Refer to DISASSEMBLY [08/2019 - ]

    for Manual Tilt and Manual Telescopic Steering Column:

    Refer to DISASSEMBLY [08/2019 - ]

    Result: 

    NG 

    See step  6

  5. READ VALUE USING TECHSTREAM (L CODE CHECK) 
    1. Replace the steering lock ECU (upper steering column with switch bracket assembly) with a new one and perform registration again.

      for Power Tilt and Power Telescopic Steering Column:

      Refer to DISASSEMBLY [08/2019 - ]

      for Manual Tilt and Manual Telescopic Steering Column:

      Refer to DISASSEMBLY [08/2019 - ]

      HINT: 

      Refer to Registration.

      Refer to REGISTRATION [08/2019 - ]

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

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      L Code Check Verification result between certification ECU (smart key ECU assembly) and steering lock ECU (upper steering column with switch bracket assembly)/
      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 steering lock ECU (upper steering column with switch bracket assembly) is not registered, or the certification ECU (smart key ECU assembly) or steering lock ECU (upper steering column with switch bracket 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 (UPPER STEERING COLUMN WITH SWITCH BRACKET ASSEMBLY) WAS DEFECTIVE) 

    Result: 

    NG 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [08/2019 - ] 

  6. CHECK HARNESS AND CONNECTOR (STEERING LOCK ECU (UPPER STEERING COLUMN WITH SWITCH BRACKET ASSEMBLY) - CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)) 
    1. Disconnect the H196 steering lock ECU (upper steering column with switch bracket assembly) connector.
    2. Disconnect the H199 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
      H196-3 (IGE) - H199-24 (SLR+) Always Below 1 Ω
      H196-3 (IGE) or H199-24 (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 (UPPER STEERING COLUMN WITH SWITCH BRACKET ASSEMBLY) 
    1. Reconnect the steering lock ECU (upper steering column with switch bracket assembly) connector.
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      H196-3 (IGE) - Body ground Always 11 to 14 V
      GTY937126Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Steering Lock ECU (Upper Steering Column with Switch Bracket Assembly))

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [08/2019 - ] 

    Result: 

    NG 

    REPLACE STEERING LOCK ECU (UPPER STEERING COLUMN WITH SWITCH BRACKET ASSEMBLY) 

    for Power Tilt and Power Telescopic Steering Column:

    Refer to DISASSEMBLY [08/2019 - ]

    for Manual Tilt and Manual Telescopic Steering Column:

    Refer to DISASSEMBLY [08/2019 - ]

  8. 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 the driver door.

      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  9

  9. 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

      The Data List item changes in accordance with the shift state.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  11

    Result: 

    OK 

    See step  10

  10. READ VALUE USING TECHSTREAM (STEERING LOCK) 
    1. Check that the steering is unlocked.
    2. Enter the following menus: Body Electrical / Smart Key / Data List.
    3. 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 (upper steering column with switch bracket 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: 

    OK 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [08/2019 - ] 

    Result: 

    NG 

    REPLACE STEERING LOCK ECU (UPPER STEERING COLUMN WITH SWITCH BRACKET ASSEMBLY) 

    for Power Tilt and Power Telescopic Steering Column:

    Refer to DISASSEMBLY [08/2019 - ]

    for Manual Tilt and Manual Telescopic Steering Column:

    Refer to DISASSEMBLY [08/2019 - ]

  11. 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.
      GTY859679Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Certification ECU (Smart Key ECU Assembly))

      Standard Voltage

      Tester Connection Condition Specified Condition
      H199-22 (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 - ] 

    Result: 

    NG 

    See step  12

  12. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - SHIFT LOCK CONTROL ECU SUB-ASSEMBLY) 
    1. Disconnect the H199 certification ECU (smart key ECU assembly) connector.
    2. Disconnect the H212 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
      H199-22 (P) - H212-11 (P2) Always Below 1 Ω
      H199-22 (P) or H212-11 (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  13

  13. CHECK SHIFT LOCK CONTROL ECU SUB-ASSEMBLY 
    1. Reconnect the certification ECU (smart key ECU assembly) connector.
      GTY859679Courtesy 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
      H199-22 (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 

    for 2WD:

    Refer to REMOVAL [08/2015 - ]

    for 4WD:

    Refer to REMOVAL [08/2015 - ]

    Result: 

    NG 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [08/2019 - ] 

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