LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Lexus >> 2021 >> GX 460 Base >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (Circuit Tests) (2 Of 2) >> SFI System >> Drive Start Control [08/2021 - ] >> Procedure
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Drive Start Control [08/2021 - ]: Procedure

  1. SYMPTOM CONFIRMATION 
    1. Interview the customer to confirm the problem.

      Result

      Result Proceed to
      Hunting A
      Hesitation/poor acceleration B

    Result: 

    B 

    See step  6

    Result: 

    A 

    See step  2

  2. PAST ACTIVATION CONFIRMATION 
    1. Check if the customer operated the vehicle in a way that would cause the drive start control to operate.

      HINT: 

      Drive Start Control Activation Conditions 

      Shift control 

      1. Activation conditions
      • Pattern A (When all of the following conditions are met, control starts.)
        • The accelerator pedal is open by approximately 1/5 or more.
        • The shift lever is moved from P to any forward position (D or S) or R.
      • Pattern B (When all of the following conditions are met, control starts.)
        • The accelerator pedal is open by approximately 1/5 or more.
        • The shift lever is moved from R to any forward position (D or S), any forward position (D or S) to R, or N to R.
          GTY922167Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      • Items Controlled
        • Engine output is restricted.
      • Deactivation Conditions
        • The accelerator pedal is released.
        • The shift lever is in P or N.

      Reverse control 

      1. Activation conditions
      • The shift lever is in R.
      • The accelerator pedal is depressed excessively.
        GTY946985Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      • Items Controlled
        • Engine output is restricted.
      • Deactivation Conditions
        • The accelerator pedal is released.
        • The shift lever is moved to any position other than R.

      HINT: 

      • The engine output restricted level differs between pattern A, pattern B and Reverse control.
      • During reverse control or shift control, engine output is adjusted based on the road gradient.

      Result

      Result Proceed to
      Performed A
      Not performed B

    Result: 

    B 

    SYSTEM NORMAL (GO TO PROBLEM SYMPTOM TABLE). Refer to  PROBLEM SYMPTOMS TABLE [08/2019 - ] 

    Result: 

    A 

    See step  3

  3. CHECK DTC OUTPUT 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: System Select / Health Check.
    5. Read the DTCs.

      Result

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

    Result: 

    B 

    GO TO DTC CHART. Refer to the appropriate service information 

    Result: 

    A 

    See step  4

  4. READ VALUE USING TECHSTREAM (FR, FL, RR, RL WHEEL SPEED) 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Start the engine.
    5. Enter the following menus: Chassis / ABS/VSC/TRAC / Data List / FR Wheel Speed, FL Wheel Speed, RR Wheel Speed and RL Wheel Speed.
    6. Read the value displayed on the Techstream.

      Standard

      Techstream Display Condition Specified Condition
      FR Wheel Speed
      FL Wheel Speed
      RR Wheel Speed
      RL Wheel Speed      		 Vehicle stopped, engine running 0 km/h (0 mph)
      Vehicle being driven at constant speed between 16.1 to 64.4 km/h (10 to 40 mph) No large fluctuations when driving at a constant speed
      WARNING:

      When performing a drive test, obey all speed limits and traffic laws.

      HINT: 

      Data can be captured relatively easily by using the snapshot function in the Data List. Confirm the data after performing the drive test.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    INSPECT FRONT OR REAR SPEED SENSOR 

    Result: 

    OK 

    See step  5

  5. READ VALUE USING TECHSTREAM (FORWARD AND REARWARD G) 
    1. Connect the Techstream to the DLC3.
    2. Start the engine.
    3. Turn the Techstream on.
    4. Enter the following menus: Chassis / ABS/VSC/TRAC / Data List / Forward and Rearward G.
    5. Read the value displayed on the Techstream.

      Standard

      Techstream Display Condition Specified Condition
      Forward and Rearward G During deceleration Value changes with vehicle speed
      During acceleration Value changes with vehicle speed
      WARNING:

      When performing a drive test, obey all speed limits and traffic laws.

      HINT: 

      Data can be captured relatively easily by using the snapshot function in the Data List. Confirm the data after performing the drive test.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    SYSTEM NORMAL (GO TO PROBLEM SYMPTOM TABLE). Refer to  PROBLEM SYMPTOMS TABLE [08/2019 - ] 

    Result: 

    NG 

    INSPECT AIRBAG ECU ASSEMBLY. Refer to  TERMINALS OF ECU [08/2019 - ] 

  6. PAST ACTIVATION CONFIRMATION 
    1. Check if the customer operated the vehicle in a way that would cause the drive start control to operate.

      HINT: 

      Drive Start Control Activation Conditions 

      Shift control 

      1. Activation conditions
      • Pattern A (When all of the following conditions are met, control starts.)
        • The accelerator pedal is open by approximately 1/5 or more.
        • The shift lever is moved from P to any forward position (D or S) or R.
      • Pattern B (When all of the following conditions are met, control starts.)
        • The accelerator pedal is open by approximately 1/5 or more.
        • The shift lever is moved from R to any forward position (D or S), any forward position (D or S) to R, or N to R.
          GTY922167Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      • Items Controlled
        • Engine output is restricted.
      • Deactivation Conditions
        • The accelerator pedal is released.
        • The shift lever is in P or N.

      Reverse control 

      1. Activation conditions
      • The shift lever is in R.
      • The accelerator pedal is depressed excessively.
        GTY946985Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      • Items Controlled
        • Engine output is restricted.
      • Deactivation Conditions
        • The accelerator pedal is released.
        • The shift lever is moved to any position other than R.

      HINT: 

      • The engine output restricted level differs between pattern A, pattern B and Reverse control.
      • During reverse control or shift control, engine output is adjusted based on the road gradient.

      Result

      Result Proceed to
      Performed A
      Not performed B

    Result: 

    A 

    SYSTEM NORMAL 

    Result: 

    B 

    See step  7

  7. CHECK DTC OUTPUT 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: System Select / Health Check.
    5. Read the DTCs.

      Result

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

    Result: 

    B 

    GO TO DTC CHART. Refer to the appropriate service information 

    Result: 

    A 

    See step  8

  8. INSPECT PARK/NEUTRAL POSITION SWITCH ASSEMBLY 
    1. Inspect the park/neutral position switch assembly.

      Refer to INSPECTION [08/2015 - ]

      Result

      Result Proceed to
      Normal A
      Abnormal B

    Result: 

    B 

    REPLACE PARK/NEUTRAL POSITION SWITCH ASSEMBLY. Refer to  REMOVAL [08/2015 - ] 

    Result: 

    A 

    See step  9

  9. READ VALUE USING TECHSTREAM (ACCEL SENS. NO. 1 VOLT % AND ACCEL SENS. NO. 2 VOLT %) 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Powertrain / Engine and ECT / Data List / Accel Sens. No. 1 Volt % and Accel Sens. No. 2 Volt %.
    5. Read the value displayed on the Techstream.

      OK

      Techstream Display Condition Specified Condition
      Accel Sens. No. 1 Volt % Accelerator Pedal Released → Depressed Values smoothly change following accelerator pedal operation
      Accel Sens. No. 2 Volt %

      HINT: 

      For numerical values of Accel Sens. No. 1 Volt % and Accel Sens. No. 2 Volt %, refer to the Data List.

      Refer to DATA LIST / ACTIVE TEST [08/2019 - ]

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    SYSTEM NORMAL (GO TO PROBLEM SYMPTOM TABLE). Refer to  PROBLEM SYMPTOMS TABLE [08/2019 - ] 

    Result: 

    NG 

    REPLACE ACCELERATOR PEDAL(W/SENSOR) ROD ASSEMBLY. Refer to  REMOVAL [08/2015 - ] 

scientia non olet · About LEMON Manuals