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Unable to Unlock Steering Wheel (Hybrid Control System cannot Start) [11/2015 - ]: Procedure

  1. CHECK DTC (ALL) 

    See step  1

    Result: 

    NG 

    REPAIR CIRCUITS INDICATED BY OUTPUT DTCS 

    Result: 

    OK 

    See step  2

  2. CHECK POWER 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 power switch with the brake pedal released causes the power source mode to change as follows:

        OK

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

    Result: 

    NG 

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

    Refer to PROBLEM SYMPTOMS TABLE [11/2015 - ] )

    Result: 

    OK 

    See step  3

  3. 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 power switch on (IG) or on (ACC) or starting hybrid control system
      NG: Except above
      • If the unlock signal has not been received, the hybrid control system 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 power switch on (ACC) or on (IG) or starting the hybrid control system, the Data List item changes to "OK".

    Result: 

    NG 

    See step  9

    Result: 

    OK 

    See step  4

  4. INSPECT CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) 
    1. Measure the voltage according to the value(s) in the table below.
      GTY735503Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TEXT IN ILLUSTRATION

      *a Component with harness connected
      (Certification ECU (Smart Key ECU Assembly))
      - -

      Standard Voltage

      Tester Connection Condition Specified Condition
      G87-25 (P) - G85-11 (E) Shift lever in P 9 V or higher
      G87-25 (P) - G85-11 (E) Shift lever not in P 1.5 V or less

    Result: 

    NG 

    See step  7

    Result: 

    OK 

    See step  5

  5. CHECK HARNESS AND CONNECTOR (POWER SOURCE TERMINAL) 
    1. Disconnect the G50 steering lock ECU connector.
    2. Measure the resistance and voltage according to the value(s) in the table below.
      GTY696803Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Condition Specified Condition
      G50-1 (GND) - Body ground Always Below 1 Ω
      NOTE:

      If the result is not as specified, check for looseness in the connection which leads to ground.

      Standard Voltage

      Tester Connection Condition Specified Condition
      G50-7 (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  6

  6. INSPECT STEERING LOCK ECU (MOTOR ACTIVATION COMMAND SIGNAL) 
    1. Reconnect the G50 steering lock ECU connector.
    2. Check the signal waveform according to the condition(s) in the table below.
      GTY723893Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      STANDARD FREQUENCY

      Item Content
      Tester Connection G50-3 (IGE) - G50-1 (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 while 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 power switch on (ACC) or on (IG) with the shift lever in P.
        • To lock the steering, turn the power switch off with the shift lever in P, and then open a door.

    Result: 

    OK 

    REPLACE STEERING LOCK ACTUATOR ASSEMBLY 

    Refer to DISASSEMBLY [11/2015 - ] )

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  7. CHECK HARNESS AND CONNECTOR (SHIFT LOCK CONTROL ECU (LOWER SHIFT LEVER ASSEMBLY) - CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)) 
    1. Disconnect the G25 shift lock control ECU (lower shift lever assembly) connector.
    2. Disconnect the G87 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
      G25-2 (P2) - G87-25 (P) Always Below 1 Ω
      G25-2 (P2) or G87-25 (P) - Body ground Always 10 kΩ higher

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  8

  8. INSPECT SHIFT LOCK CONTROL ECU (LOWER SHIFT LEVER ASSEMBLY) 
    1. Reconnect the G25 shift lock control ECU (lower shift lever assembly) connector.
    2. Measure the voltage according to the value(s) in the table below.
      GTY708963Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Voltage

      Tester Connection Condition Specified Condition
      G25-2 (P2) - Body ground Shift lever in P 9 V or higher
      G25-2 (P2) - Body ground Shift lever not in P 1.5 V or less
      TEXT IN ILLUSTRATION

      *a Component with harness connected
      (Shift Lock Control ECU (Lower Shift Lever Assembly))

    Result: 

    OK 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) 

    Refer to REMOVAL [11/2015 - ] )

    Result: 

    NG 

    REFER TO SHIFT LEVER (INSPECTION) 

    Refer to REMOVAL [11/2015 - ] )

  9. READ VALUE USING TECHSTREAM (S CODE CHECK) 

    See step  6

    Result: 

    NG 

    See step  12

    Result: 

    OK 

    See step  10

  10. READ VALUE USING TECHSTREAM (L CODE CHECK) 

    See step  7

    Result: 

    NG 

    See step  13

    Result: 

    OK 

    See step  11

  11. REPLACE STEERING LOCK ACTUATOR ASSEMBLY 

    See step  8

    Result: 

    OK 

    END 

    Result: 

    NG 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) 

    Refer to REMOVAL [11/2015 - ] )

  12. REPLACE ID CODE BOX (IMMOBILISER CODE ECU) 

    See step  9

    Result: 

    OK 

    END 

    Result: 

    NG 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) 

    Refer to REMOVAL [11/2015 - ] )

  13. REPLACE ID CODE BOX (IMMOBILISER CODE ECU) 

    See step  10

    Result: 

    OK 

    END 

    Result: 

    NG 

    REPLACE STEERING LOCK ACTUATOR ASSEMBLY 

    Refer to DISASSEMBLY [11/2015 - ] )