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System Outline

The cruise control system is a constant vehicle speed controller in which the engine output and motor drive torque are controlled automatically with control of the switch at hand without depressing the accelerator pedal when a driver wishes to drive at a constant speed on a highway.

  1. Constant Speed Control 

    When actual vehicle speed is faster than the set vehicle speed, a signal is sent to the HV control motor to rotate in order to decrease the driving force. On the contrary, when the vehicle speed is slower than the set vehicle speed, a signal is sent to the HV control motor to rotate in order to increase the driving force.

  2. Setting 

    When operating the - SET SW with the ON-OFF SW ON (Within the settable range of the vehicle speed: Above the low speed limit and below the high speed limit), the vehicle speed at which the switch is turned OFF is stored in the memory and the vehicle is controlled to drive constantly at that speed.

  3. Coast, Tap Down 

    < Coast >

    When the - SET SW is kept ON during driving under the cruise control, the coast control makes the cruise control request controlling 'Zero' to decelerate and stores the vehicle speed in the memory at which the switch is turned OFF and controls the vehicle to drive constantly at that speed.

    < Tap down >

    When the - SET SW is turned ON momentarily (Approx. 0.5 sec.), the set vehicle speed decelerates in approximately 1.6 km/h steps by each switch operation. In the tap down operation with more than 5 km/h difference between the set vehicle speed and actual vehicle speed, the vehicle speed at which the switch is turned OFF is stored in the memory and the vehicle is controlled to drive constantly at that speed.

  4. Acceleration, Tap Up 

    < Acceleration >

    When the + RES SW is kept ON during driving under the cruise control, the acceleration control rotates the HV control motor to increase the driving force to control the vehicle to accelerate with constant acceleration. The vehicle speed at which the switch is turned OFF is stored in the memory and the vehicle is controlled to drive constantly at that speed.

    < Tap up >

    When the - SET SW is turned ON momentarily (Approx. 0.5 sec.), the set vehicle speed accelerates in approximately 1.6 km/h steps by each switch operation. When difference between the set vehicle speed and actual vehicle speed is more than 5 km/h, the tap up operation does not change the set vehicle speed.

  5. Low Speed Limit 

    It means the lower limit speed in the settable speed range and is set to be approximately 40 km/h. The cruise control cannot be set if the vehicle speed is slower than the low speed limit. When the vehicle speed drops below the low speed limit during driving under the cruise control, the cruise control is automatically cancelled.

  6. High Speed Limit 

    It means the higher limit speed in the settable speed range and is set to be approximately 100 km/h for the domestic and 200 km/h for the other destinations. The cruise control cannot be set if the vehicle speed is faster than the high speed limit. The vehicle cannot be accelerated above the high speed limit with the + RES SW operation.

  7. Cancel 

    When the following signals are input during driving under the cruise control, the cruise control is cancelled.

    1. Stop lamp switch ON
    2. D position circuit ON to OFF in the park/neutral position switch
    3. When selecting other gear positions than D or 3 range in the shift lever in M position
    4. CANCEL SW ON in the control switch
    5. ON-OFF SW OFF
  8. Resume 

    When the vehicle speed stays above the low speed limit after the cruise control is canceled with above signals, the cruise control resumes operation to reach the vehicle speed that was set at the time the driver canceled the cruise control with constant acceleration by operating the + RES SW from OFF to ON.

  9. Over Drive Control 

    Over-drive may be cut in climbing a hill during cruise control traveling. When climbing a hill is judged to finish from the throttle opening information under the over-drive ineffective condition, the over-drive function resumes automatically after the set time for over-drive resuming. However, when the vehicle speed drops below the over-drive resuming vehicle speed before the set time for over-drive resuming, the set time is reset and will work again from when the vehicle speed reaches the over-drive resuming vehicle speed.

  10. Auto Cancel 
    1. The set vehicle speed is erased in the memory and the cruise control is cancelled in the following conditions. Until the ON-OFF SW is turned ON again, the cruise operation indicator blinks and the control will not be effective.
      1. When the stop lamp switch is disconnected and short-circuit.
      2. When the vehicle speed signal is abnormal
      3. When the electronic throttle parts are abnormal
    2. The set vehicle speed is erased in the memory and the cruise control is cancelled in the following conditions. Until the ON-OFF SW is turned ON again, the cruise operation indicator blinks and the control will not be effective unless the power switch is turned OFF.
      1. When the stop lamp switch input circuit is abnormal
      2. When the cancel circuit is abnormal
    3. The set vehicle speed is erased in the memory and the cruise control is cancelled in the following conditions.
      1. When the vehicle speed reaches below the low speed limit (Approx. 40 km/h).
      2. When the vehicle speed reaches the speed slower than (The set vehicle speed minus 16 km/h).
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