LEMON Manuals: Even more car manuals for everyone
Home >> Lexus >> 2025 >> NX 350h >> Repair and Diagnosis >> External Pages >> Different car >> Section 61 (Smart Access System (For Start) - Symptom Tests (2 Of 2)) >> SMART ACCESS SYSTEM WITH PUSH-BUTTON START (for Start Function, Gasoline Model) >> Steering Lock does not Lock [11/2021 - 03/2023] >> Procedure

Steering Lock does not Lock [11/2021 - 03/2023]: Procedure

WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2025 Lexus NX 350, 2025 Lexus NX 250, 2024 Lexus NX 350, 2024 Lexus NX 250, and 2023 Lexus NX 350. However, it is still accessible from the selected car via links, so may be relevant.
  1. READ VALUE USING GTS (STEERING LOCK REQUEST RECEIVE) 
    1. Read the Data List according to the display on the GTS.

      Body Electrical > Smart Access > Data List 

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      Steering Lock Request Receive Status of steering lock command from certification ECU (smart key ECU assembly) OK or NG OK: Certification ECU (smart key ECU assembly) sends steering lock command (within 10 seconds of any door opened with shift position in P and ignition switch off)
      NG: Certification ECU (smart key ECU assembly) does not send steering lock command (no door opened with shift position in P and ignition switch off)      		 If OK is not displayed even though the steering lock conditions are met, the certification ECU (smart key ECU assembly) may be malfunctioning.

      Body Electrical > Smart Access > Data List 

      Tester Display
      Steering Lock Request Receive

      OK

      The certification ECU (smart key ECU assembly) receives a lock request signal within 10 seconds of turning the ignition switch from ON to ACC or off and opening a door with the shift position in P, and OK is displayed on the GTS screen.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  10

    Result: 

    OK 

    See step  2

  2. READ VALUE USING GTS (S CODE CHECK) 
    1. Read the Data List according to the display on the GTS.

      Body Electrical > Smart Access > Data List 

      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 (immobilizer 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 (immobilizer code ECU) is not registered, or the certification ECU (smart key ECU assembly) or ID code box (immobilizer code ECU) is malfunctioning.
      • The steering cannot be locked.
      • The steering cannot be unlocked (the engine cannot be started).

      Body Electrical > Smart Access > Data List 

      Tester Display
      S Code Check

      OK

      OK is displayed on the GTS.

      HINT: 

      Reasons for verification failure:

      • The certification ECU (smart key ECU assembly) or ID code box (immobilizer code ECU) is malfunctioning.
      • There is a problem with the communication between ECUs.
      • An ECU was replaced, but not registered.
      • An ECU was replaced with an ECU which has already been registered to another vehicle.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  9

    Result: 

    OK 

    See step  3

  3. READ VALUE USING GTS (L CODE CHECK) 
    1. Read the Data List according to the display on the GTS.

      Body Electrical > Smart Access > Data List 

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      L Code Check Verification result between ID code box (immobilizer code ECU) and steering lock ECU (steering lock actuator with ECU assembly) OK or NG OK: Verification result normal
      NG: Verification result abnormal      		 When NG is displayed:
      • The ID code for the ID code box (immobilizer code ECU) or steering lock ECU (steering lock actuator with ECU assembly) is not registered, or the ID code box (immobilizer code ECU) or steering lock ECU (steering lock actuator with ECU assembly) is malfunctioning.
      • The steering cannot be locked.
      • The steering cannot be unlocked (the engine cannot be started).

      Body Electrical > Smart Access > Data List 

      Tester Display
      L Code Check

      OK

      OK is displayed on the GTS.

      HINT: 

      Reasons for verification failure:

      • The steering lock ECU (steering lock actuator with ECU 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  8

    Result: 

    OK 

    See step  4

  4. CHECK HARNESS AND CONNECTOR (POWER SOURCE) 
    1. Disconnect the D61 steering lock ECU (steering lock actuator with ECU assembly) connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      D61-1 (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
      D61-7 (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  5

  5. CHECK STEERING LOCK ECU (STEERING LOCK ACTUATOR WITH ECU ASSEMBLY) 
    1. Connect the D61 steering lock ECU (steering lock actuator with ECU assembly) connector.
      GTY1059968Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Steering lock ECU (steering lock actuator with ECU assembly))
      *b Waveform
      *c Steering lock motor not operating
      *d Steering lock motor operating
    2. Check the signal waveform according to the condition(s) in the table below.
      Tester Connection Condition Tool Setting Specified Condition
      D61-3 (IGE) - D61-1 (GND) Steering lock motor operating when all conditions met, and then door opened:
      • Shift position in P
      • Steering unlocked
      • Ignition switch turned off
      		 2 V/DIV., 200 ms./DIV. Pulse generation
      (See waveform)

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE STEERING LOCK ECU (STEERING LOCK ACTUATOR WITH ECU ASSEMBLY) 

    for Power Tilt and Power Telescopic Steering Column: Refer to DISASSEMBLY [11/2021 - ]

    for Manual Tilt and Manual Telescopic Steering Column: Refer to DISASSEMBLY [11/2021 - 03/2023]

    Result: 

    NG 

    See step  6

  6. CHECK HARNESS AND CONNECTOR (STEERING LOCK ECU (STEERING LOCK ACTUATOR WITH ECU ASSEMBLY) - CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)) 
    1. Disconnect the D61 steering lock ECU (steering lock actuator with ECU assembly) connector.
    2. Disconnect the D58 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
      D61-3 (IGE) - D58-24 (SLR+) Always Below 1 Ω
      D61-3 (IGE) or D58-24 (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 (STEERING LOCK ACTUATOR WITH ECU ASSEMBLY) 
    1. Connect the D61 steering lock ECU (steering lock actuator with ECU assembly) connector.
      GTY1059259Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Steering lock ECU (steering lock actuator with ECU assembly))
    2. Connect the D58 certification ECU (smart key ECU assembly) connector.
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      D61-3 (IGE) - Body ground Always 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [11/2021 - ] 

    Result: 

    NG 

    REPLACE STEERING LOCK ECU (STEERING LOCK ACTUATOR WITH ECU ASSEMBLY) 

    for Power Tilt and Power Telescopic Steering Column: Refer to DISASSEMBLY [11/2021 - ]

    for Manual Tilt and Manual Telescopic Steering Column: Refer to DISASSEMBLY [11/2021 - 03/2023]

  8. CHECK STEERING LOCK ECU (STEERING LOCK ACTUATOR WITH ECU ASSEMBLY) 
    1. Replace the steering lock ECU (steering lock actuator with ECU assembly) with a new one and perform registration.

      Refer to REGISTRATION [11/2021 - ]

      HINT: 

      For replacement.

      for Power Tilt and Power Telescopic Steering Column: Refer to DISASSEMBLY [11/2021 - ]

      for Manual Tilt and Manual Telescopic Steering Column: Refer to DISASSEMBLY [11/2021 - 03/2023]

    2. Read the Data List according to the display on the GTS.

      Body Electrical > Smart Access > Data List 

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      L Code Check Verification result between ID code box (immobilizer code ECU) and steering lock ECU (steering lock actuator with ECU assembly) OK or NG OK: Verification result normal
      NG: Verification result abnormal      		 When NG is displayed:
      • The ID code for the ID code box (immobilizer code ECU) or steering lock ECU (steering lock actuator with ECU assembly) is not registered, or the ID code box (immobilizer code ECU) or steering lock ECU (steering lock actuator with ECU assembly) is malfunctioning.
      • The steering cannot be locked.
      • The steering cannot be unlocked (the engine cannot be started).

      Body Electrical > Smart Access > Data List 

      Tester Display
      L Code Check

      OK

      OK is displayed on the GTS.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    END (STEERING LOCK ECU (STEERING LOCK ACTUATOR WITH ECU ASSEMBLY) WAS DEFECTIVE) 

    Result: 

    NG 

    REPLACE ID CODE BOX (IMMOBILIZER CODE ECU). Refer to  REMOVAL [11/2021 - ] 

  9. CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) 
    1. Replace the certification ECU (smart key ECU assembly) with a new one and perform registration.

      Refer to REGISTRATION [11/2021 - ]

    2. Read the Data List according to the display on the GTS.

      Body Electrical > Smart Access > Data List 

      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 (immobilizer 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 (immobilizer code ECU) is not registered, or the certification ECU (smart key ECU assembly) or ID code box (immobilizer code ECU) is malfunctioning.
      • The steering cannot be locked.
      • The steering cannot be unlocked (the engine cannot be started).

      Body Electrical > Smart Access > Data List 

      Tester Display
      S Code Check

      OK

      OK is displayed on the GTS.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    END (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) WAS DEFECTIVE) 

    Result: 

    NG 

    REPLACE ID CODE BOX (IMMOBILIZER CODE ECU). Refer to  REMOVAL [11/2021 - ] 

  10. READ VALUE USING GTS (DOOR COURTESY SWITCH STATUS) 
    1. Using the GTS, check the following main body ECU (multiplex network body ECU) Data List item by opening and closing each door to confirm the state of each door courtesy light switch.

      Body Electrical > Main Body > Data List 

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      FR Door Courtesy Switch Status Front door RH courtesy light switch signal OFF or ON OFF: Front door RH closed
      ON: Front door RH open      		 -
      FL Door Courtesy Switch Status Front door LH courtesy light switch signal OFF or ON OFF: Front door LH closed
      ON: Front door LH open      		 -
      RR Door Courtesy Switch Status Rear door RH courtesy light switch signal OFF or ON OFF: Rear door RH closed
      ON: Rear door RH open      		 -
      RL Door Courtesy Switch Status Rear door LH courtesy light switch signal OFF or ON OFF: Rear door LH closed
      ON: Rear door LH open      		 -

      Body Electrical > Main Body > Data List 

      Tester Display
      FR Door Courtesy Switch Status
      FL Door Courtesy Switch Status
      RR Door Courtesy Switch Status
      RL Door Courtesy Switch Status

      OK

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

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    GO TO E-LATCH SYSTEM (Door Courtesy Switch Circuit). Refer to  Door Courtesy Switch Circuit [11/2021 - ] 

    Result: 

    OK 

    See step  11

  11. READ VALUE USING GTS (SHIFT P SIGNAL CONDITION (LINE)) 
    1. Move the shift position to P.
    2. Read the Data List according to the display on the GTS.

      Body Electrical > Power Source Control > Data List 

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      Shift P Signal Condition (Line) Shift position P Shift P, Other than shift P, Shift N or Other than shift P/N Shift P: Shift position in P
      Shift N: Shift position in N
      Other than shift P/N: Other than shift position in P or N      		 Use this item to determine if the shift position switch is malfunctioning.

      Body Electrical > Power Source Control > Data List 

      Tester Display
      Shift P Signal Condition (Line)

      OK

      ON is displayed on the GTS.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  13

    Result: 

    OK 

    See step  12

  12. READ VALUE USING GTS (STEERING LOCK REQUEST RECEIVE) 
    1. Replace the certification ECU (smart key ECU assembly) with a new one and perform registration.

      Refer to REGISTRATION [11/2021 - ]

    2. Read the Data List according to the display on the GTS.

      Body Electrical > Smart Access > Data List 

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      Steering Lock Request Receive Status of steering lock command from certification ECU (smart key ECU assembly) OK or NG OK: Certification ECU (smart key ECU assembly) sends steering lock command (within 10 seconds of any door opened with shift position in P and ignition switch off)
      NG: Certification ECU (smart key ECU assembly) does not send steering lock command (no door opened with shift position in P and ignition switch off)      		 If OK is not displayed even though the steering lock conditions are met, the certification ECU (smart key ECU assembly) may be malfunctioning.

      Body Electrical > Smart Access > Data List 

      Tester Display
      Steering Lock Request Receive

      OK

      Within 10 seconds after any of the doors is opened with shift position in P and ignition switch off, the Data List item changes to "OK".

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    END (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) WAS DEFECTIVE) 

    Result: 

    NG 

    REPLACE ID CODE BOX (IMMOBILIZER CODE ECU). Refer to  REMOVAL [11/2021 - ] 

  13. CHECK TRANSMISSION FLOOR SHIFT ASSEMBLY 
    1. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      D58-14 (P) - Body ground Ignition switch ACC → ignition switch ON and Shift position in P Pulse generation (24 to 25 Hz or 30 to 31 Hz, High voltage: 9 V or more, Low voltage: below 1 V, duty ratio: 25 %)
      Ignition switch ACC → ignition switch ON and Shift position in N Pulse generation (24 to 25 Hz or 30 to 31 Hz, High voltage: 9 V or more, Low voltage: below 1 V, duty ratio: 55 %)
      Ignition switch ACC → ignition switch ON and Shift position in other then P or N Pulse generation (24 to 25 Hz or 30 to 31 Hz, High voltage: 9 V or more, Low voltage: below 1 V, duty ratio: 40 %)
      GTY1058364Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Certification ECU (Smart Key ECU Assembly))

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [11/2021 - ] 

    Result: 

    NG 

    See step  14

  14. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - TRANSMISSION FLOOR SHIFT ASSEMBLY) 
    1. Disconnect the D58 certification ECU (smart key ECU assembly) connector.
    2. Disconnect the D39 transmission floor shift assembly connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      D58-14 (P) - D39-7 (PPOS) Always Below 1 Ω
      D58-14 (P) or D39-7 (PPOS) - Other terminals and body ground Always 10 kΩ or higher
    4. Reconnect the D58 certification ECU (smart key ECU assembly) connector.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE TRANSMISSION FLOOR SHIFT ASSEMBLY 

    for UA81F: Refer to DISASSEMBLY [11/2021 - ]

    for UB80E or UB80F: Refer to DISASSEMBLY [11/2021 - ]

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

scientia non olet · About LEMON Manuals