CRUISE CONTROL SYSTEM GENERAL


  1. OUTLINE


    1. The cruise control system has 2 modes: the constant speed control mode and the speed limiter control mode. The cruise control system is controlled by the ECM.

    2. A cruise control system without the speed limiter control and a cruise control system with the speed limiter control are both available on the models with manual transaxle or the models with automatic transaxle. On the models with Continuously Variable Transmission (CVT), the cruise control system with the speed limiter control is not available.

    3. On the models with gasoline engine, the cruise control system effects control through the Electronic Throttle Control System-intelligent (ETCS-i). In the constant speed control mode, once the cruise control system is set to the desired vehicle speed, the throttle valve position is adjusted automatically to maintain the vehicle speed without depressing the accelerator pedal. The ECM compares the actual vehicle speed and the set speed. If the vehicle speed is higher than the set speed, the ECM activates the throttle control motor in the throttle closing direction. If the vehicle speed is lower than the set speed, the ECM activates the throttle motor in the throttle opening direction.

    4. On the models with diesel engine, the cruise control system effects control through the ECD system. In the constant speed control mode, once the cruise control system is set to the desired vehicle speed, the fuel injection volume is adjusted automatically to maintain the vehicle speed without depressing the accelerator pedal. The ECM compares the actual vehicle speed and the set speed. If the vehicle speed is higher than the set speed, the ECM decreases the fuel injection volume by regulating the 4 fuel injectors via the injector driver*1 or ECM*2. If the vehicle speed is lower than the set speed, the ECM increases the fuel injection volume by regulating the 4 fuel injectors via the injector driver*1 or ECM*2.

    5. In the speed limiter control mode, the cruise control system prevents the vehicle from accelerating higher than the limit speed when the driver depresses the accelerator pedal assembly. This control is effected through the use of the speed limiter main switch and the cruise control switch.

    6. The cruise control system is controlled by the ECM*1 or driving support ECU assembly*2.


      • *1: Except models with 1WW engine

      • *2: Models with 1WW engine

  2. PRECAUTION


    1. Observe the following precautions when using the constant speed control:


      1. Turn the main switch off when the constant speed control is not being used.

      2. Beware of a possible increase in vehicle speed when driving downhill (if the vehicle speed increases excessively, cancel the constant speed control and shift down to decelerate with the engine brake).

      3. If the cruise main indicator light turns off while the constant speed control is on, first turn the constant speed control off. Then, turn the constant speed control back on. If the cruise main indicator light continues to turns off after performing the above, there may be a malfunction in the system. Although this does not affect normal driving, have the vehicle inspected at a Toyota dealer.

    2. Do not use the constant speed control under the following road and vehicle conditions:


      1. Road with heavy traffic

      2. Steep hills

      3. Road with sharp bends

      4. Winding road

      5. Frozen or snowy road

      6. Slippery road surface

      7. Towing trailer

    3. Observe the following precautions when using the speed limiter control:


      1. Turn the speed limiter main switch off when the speed limiter control is not being used.

      2. Beware of a possible increase in vehicle speed when driving downhill (if the vehicle speed increases excessively, shift down to decelerate with the engine brake).

      3. If the speed limiter main indicator light turns off while the speed limiter control is on, first turn the speed limiter control off. Then, turn the speed limiter control back on. If the speed limiter main indicator light continues to turns off after performing the above, there may be a malfunction in the system. Although this does not affect normal driving, have the vehicle inspected at a Toyota dealer.

    4. Do not use the speed limiter control under the following road and vehicle conditions:


      1. Steep hills

      2. Frozen or snowy road

      3. Slippery road surface

      4. Towing trailer