SPEED LIMITER SYSTEM


  1. FUNCTION OF MAIN COMPONENTS


    1. The main components in the speed limiter system have the following functions:

      Component Function
      Speed Limiter Switch Turns speed limiter control on and off.
      Cruise Control Switch CANCEL Switch A cancel signal is output to the hybrid vehicle control ECU when this switch is operated.
      RES/+ Switch Increases the limit speed or resumes a preset limit speed.
      SET/- Switch The deceleration function and set control function can be performed by operating this switch. A signal is output to the hybrid vehicle control ECU when this switch is operated.
      Hybrid Vehicle Control ECU

      • Controls the speed limiter system in accordance with signals from the switches and sensors.

      • If the hybrid vehicle control ECU detects a malfunction in the speed limiter system, it will store a Diagnostic Trouble Code (DTC).
      Combination Meter Assembly Speed Limiter Indicator Light

      • Based on a speed limiter indicator light operation signal sent by the hybrid vehicle control ECU, the combination meter assembly illuminates the speed limiter indicator light in green when the speed limiter switch has been pressed to turn the speed limiter system on.

      • Based on a speed limiter indicator light operation signal sent by the hybrid vehicle control ECU assembly, the combination meter assembly turns off the speed limiter indicator light if a malfunction occurs in the speed limiter system.
      Main Display Displays the limit speed when a limit speed is set.
      Multi-information Display Displays a warning message to alert the driver in accordance with a signal provided by the hybrid vehicle control ECU.
      ECM Actuates the throttle control motor in accordance with the signals from the hybrid vehicle control ECU.
      Throttle Body Assembly Throttle Control Motor Adjusts the throttle valve opening angle in accordance with signals from the ECM.
      Throttle Position Sensor Detects the throttle valve opening angle and outputs it to the ECM.
      Brake Booster with Master Cylinder Assembly Skid Control ECU Transmits the speed signal to the hybrid vehicle control ECU.
      Speed Sensors Detects the wheel speed of each of the 4 wheels.
      Accelerator Pedal Sensor Assembly Detects depressing of the accelerator pedal, whether the depressing of the accelerator pedal has exceeded the kick down mode threshold and transmits signals to the hybrid vehicle control ECU.
      Combination Switch Assembly VSC OFF (TRC OFF) Switch Detects the VSC (TRC) off signal and outputs it to the skid control ECU.
      Network Gateway ECU Gateway function of CAN communication.

  2. FUNCTION


    1. The speed limiter system has the following functions:

      Function Outline
      Set Control When the driver turns on the speed limiter switch, the speed limiter indicator light will illuminate in the combination meter assembly. In this state, when the cruise control switch is pressed in the SET/- direction, the system will memorize the speed that the vehicle was traveling at prior to the operation of the cruise control switch as a limit speed, and display the limit speed on the combination meter assembly (If the cruise control switch is pressed in the SET/- direction while the vehicle is being driven at 30 km/h [19 mph] or less, or while the vehicle is stopped, the system will memorize the limit speed as being approximately 30 km/h [19 mph]).
      Constant Speed Control When the speed limiter control system is on, the hybrid vehicle control ECU will compare the actual vehicle speed with the limit speed. If the actual vehicle speed is greater than the limit speed, the hybrid vehicle control ECU will control the engine and MG2, Thus, the system reduces the actual vehicle speed to the limit speed.
      Coast Control If the driver continues to press the cruise control switch in the SET/- direction, the system will reduce the limit speed in 5 km/h or 5 mph increments. The instant the driver releases the cruise control switch, that speed will be rendered as the set speed.
      Tap-down Control If the driver presses the cruise control switch momentarily (approximately 0.6 seconds) in the SET/- direction, the system will reduce the limit speed by 1 km/h or 1 mph with each press of the switch.
      Accelerator Control If the driver continues to press the cruise control switch in the RES/+ direction, the system will increase the limit speed in 5 km/h or 5 mph increments. The instant the driver releases the cruise control switch, that speed will be rendered as the limit speed.
      Tap-up Control If the driver presses the cruise control switch momentarily (approximately 0.6 seconds) in the RES/+ direction, the system will increase the limit speed by 1 km/h or 1 mph with each press of the switch.
      Override Control While driving the vehicle with speed limiter system on, if the driver fully depresses the accelerator pedal, the hybrid vehicle control ECU will detect that the accelerator pedal position sensor is in kick down mode. Then, the hybrid vehicle control ECU will recognize this to be the driver's acceleration requirement, and allow the vehicle to accelerate higher than the limit speed. After the acceleration, when the vehicle speed falls below the limit speed, this function will resume limit speed control.
      Cancel Control

      While the vehicle is being driven with speed limiter system on, if any one of the following signals is input into the hybrid vehicle control ECU, the system will cancel speed limiter system:


      • CANCEL switch on signal (the driver has pressed the cruise control switch in the CANCEL direction).

      • Speed limiter switch off signal (deletes the limit speed).

      • Cruise control switch on signal (transfers to the constant speed control mode, turns off the speed limiter indicator light, and deletes the limit speed).

      • Malfunction in the hybrid system.

      • When the VSC or TRC system is turned off by pressing the VSC OFF switch.

      • Malfunction in the vehicle speed.

      • Communication malfunction between the skid control ECU.
      Resume Control After turning the CANCEL switch on to turn speed limiter control switch off, if the driver pushes the cruise control switch in the RES/+ direction, the system will limit the vehicle speed at the limit speed that was set at the time of cancelation.

  3. DIAGNOSIS


    1. If a malfunction occurs in the speed limiter system during speed limit control operation, the hybrid vehicle control ECU automatically cancel control and turn off the speed limiter indicator light. At this time, "Check Speed Limiiter System" is displayed on the multi-information display. the hybrid vehicle control ECU stores the malfunction in the form of a Diagnostic Trouble Code (DTC).

    2. The DTCs can be read by connecting the Global TechStream (GTS) to the DLC3. For details, refer to the Repair Manual.