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Unable to Unlock Steering Wheel (Hybrid Control System cannot Start) [12/2013 - ]: Procedure

  1. CHECK DTC (ALL) See step   1 

    NG → REPAIR CIRCUITS INDICATED BY OUTPUT DTCS 

    OK: Go to next step 

  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

    NG → See step   13 

    OK: Go to next step 

  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 (immobilizer 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".

    NG → See step   6 

    OK: Go to next step 

  4. 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.
      GTY336028Courtesy 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))

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  5. 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.
      GTY336280Courtesy 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.

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   11 

  6. READ VALUE USING TECHSTREAM (S CODE CHECK) See step   6 

    NG → See step   9 

    OK: Go to next step 

  7. READ VALUE USING TECHSTREAM (L CODE CHECK) See step   7 

    NG → See step   10 

    OK: Go to next step 

  8. REPLACE STEERING LOCK ACTUATOR ASSEMBLY See step   8 

    NG → See step   12 

    OK → END 

  9. REPLACE ID CODE BOX (IMMOBILIZER CODE ECU) See step   9 

    NG → See step   12 

    OK → END 

  10. REPLACE ID CODE BOX (IMMOBILIZER CODE ECU) See step   10 

    NG → See step   11 

    OK → END 

  11. REPLACE STEERING LOCK ACTUATOR ASSEMBLY. Refer to  DISASSEMBLY [12/2013 - ] 
  12. REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [12/2013 - ] 
  13. GO TO SMART KEY SYSTEM (for Start Function) (PROBLEM SYMPTOMS TABLE). Refer to  PROBLEM SYMPTOMS TABLE [12/2013 - ]