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Unable to Unlock Steering Wheel (Engine cannot Start) [08/2015 - ]: Procedure

  1. CHECK ENGINE SWITCH (SWITCH CONDITION) 
    1. Check the power source mode change.
      1. When the key is inside the vehicle and the shift lever is in P, check that pressing the engine switch with the brake pedal released causes the power source mode to change as follows:

        OK

        Off → on (ACC) → on (IG) → off

    Result: 

    NG 

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

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

    Result: 

    OK 

    See step  2

  2. CHECK INDICATOR 
    1. With the engine switch on (IG), check that Steering Lock active is displayed on the multi-information display in the combination meter assembly.
      RESULT

      Result Proceed to
      Steering Lock active is displayed. A
      Steering Lock active is not displayed. B

    Result: 

    B 

    See step  4

    Result: 

    A 

    See step  3

  3. CHECK STEERING UNLOCK 
    1. While turning the steering wheel left and right, press the engine switch.
    2. Check that the steering is unlocked.
      RESULT

      Result Proceed to
      The steering is unlocked. A
      The steering is not unlocked. B

    Result: 

    A 

    END 

    Result: 

    B 

    See step  4

  4. CHECK FOR DTC 
    1. Using the Techstream, check if the certification ECU (smart key ECU assembly) DTC is output.
      RESULT

      Result Proceed to
      DTCs are not output. A
      DTCs are output. B

    Result: 

    B 

    GO TO DIAGNOSTIC PROCEDURE INDICATED BY OUTPUT DTC 

    Result: 

    A 

    See step  5

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

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Unlock Request Receive Reception state of steering unlock 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 turning engine switch on (IG) or on (ACC) or starting engine
      NG: Except above
      • If the unlock signal has not been received, the engine cannot be started.
      • If this item does not change to "OK" even though the steering unlock conditions are met, the certification ECU (smart key ECU assembly) may be malfunctioning.

      OK

      Within 10 seconds of turning the engine switch on (ACC) or on (IG) or starting the engine, the Data List item changes to "OK".

    Result: 

    NG 

    See step  11

    Result: 

    OK 

    See step  6

  6. READ VALUE USING TECHSTREAM (S CODE CHECK) 

    See step  2

    Result: 

    NG 

    See step  14

    Result: 

    OK 

    See step  7

  7. READ VALUE USING TECHSTREAM (L CODE CHECK) 

    See step  3

    Result: 

    NG 

    See step  15

    Result: 

    OK 

    See step  8

  8. INSPECT STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY) 
    1. 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 Component with harness connected
      (Steering Lock ECU (Steering Lock Actuator Assembly))

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  9

  9. 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  10

  10. INSPECT STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY) 
    1. Reconnect the E26 steering lock ECU (steering lock actuator assembly) connector.
    2. Check the signal waveform according to the condition(s) in the table below.
      GTY575232Courtesy 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  16

  11. INSPECT STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY) 
    1. Measure the voltage according to the value(s) in the table below.
      GTY577658Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Voltage

      Tester Connection Condition Specified Condition
      E26-4 (SLP1) - Body ground Always 11 to 14 V
      TEXT IN ILLUSTRATION

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

    Result: 

    NG 

    See step  18

    Result: 

    OK 

    See step  12

  12. READ VALUE USING TECHSTREAM (STEERING UNLOCK) 
    1. Check that the steering is locked.
    2. Read the Data List according to the display on the Techstream.
      SMART KEY

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Steering Unlock 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  13

  13. READ VALUE USING TECHSTREAM (UNLOCK REQUEST RECEIVE) 
    1. Replace the certification ECU (smart key ECU 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. Turn the engine switch on (IG).
    4. Use the Data List to check if the steering lock request is functioning properly.
      SMART KEY

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Unlock Request Receive Unlock request signal received state / OK or NG OK: Unlock request signal received within 10 seconds of engine switch on (IG) or on (ACC), or of a engine start operation being performed
      NG: Engine switch not turned on (IG) or on (ACC), and engine start operation not performed
      • 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 turning the engine switch on (ACC) or on (IG) or starting the engine, the Data List item changes to "OK".

    Result: 

    OK 

    END 

    Result: 

    NG 

    REPLACE ID CODE BOX (IMMOBILISER CODE ECU) 

    (Refer to REMOVAL [08/2015 - ] )

  14. REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) 

    See step  11

    Result: 

    OK 

    END 

    Result: 

    NG 

    REPLACE ID CODE BOX (IMMOBILISER CODE ECU) 

    (Refer to REMOVAL [08/2015 - ] )

  15. REPLACE STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY) 

    See step  12

    Result: 

    OK 

    END 

    Result: 

    NG 

    REPLACE ID CODE BOX (IMMOBILISER CODE ECU) 

    (Refer to REMOVAL [08/2015 - ] )

  16. 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  17

  17. INSPECT STEERING LOCK ECU (STEERING LOCK ACTUATOR ASSEMBLY) 
    1. Reconnect the E26 steering lock ECU (steering lock actuator assembly) connector.
    2. Reconnect the E151 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 - ] )

  18. 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 E26 steering lock ECU (steering lock actuator assembly) connector.
    3. Disconnect the E151 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
      E26-4 (SLP1) - E125-23 (SLP) Always Below 1 Ω
      E26-4 (SLP1) or E125-23 (SLP) - Body ground Always 10 kΩ or higher

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  19

  19. READ VALUE USING TECHSTREAM (UNLOCK REQUEST RECEIVE) 
    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. Turn the engine switch on (IG).
    4. Use the Data List to check if the steering lock request is functioning properly.
      SMART KEY

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Unlock Request Receive Unlock request signal received state / OK or NG OK: Unlock request signal received within 10 seconds of engine switch on (IG) or on (ACC), or of a engine start operation being performed
      NG: Engine switch not turned on (IG) or on (ACC), and engine start operation not performed
      • 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 turning the engine switch on (ACC) or on (IG) or starting the engine, the Data List item changes to "OK".

    Result: 

    OK 

    END 

    Result: 

    NG 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) 

    (Refer to REMOVAL [08/2015 - ] )

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