CRUISE CONTROL SYSTEM SYSTEM DESCRIPTION


  1. CRUISE CONTROL SYSTEM

    This system is controlled by the ECM, and is actuated by the throttle body. The ECM controls the following functions: ON-OFF, -SET, +/RES, CANCEL, vehicle speed operation, motor output control, and shift down control.


    • The ECM compares the driving vehicle speed from the vehicle speed sensor with the stored vehicle speed set through the cruise control switch. The ECM controls the throttle motor of the throttle body to open the valve when the driving speed is less than the stored speed.

    • The ECM receives signals such as ON-OFF, -SET, +RES, and CANCEL from the cruise control switch and executes the corresponding function.

    • The ECM illuminates the CRUISE main indicator light on the combination meter when it receives the cruise control switch on signal.

    • The ECM cancels the cruise control system when the brake pedal is depressed and the ECM receives the stop light switch signal.

    • for CVT:

      The ECM receives the park/neutral position switch signal and cancels the cruise control system when the shift lever is moved from D or S with the S4 range selected to a position other than D or S with the S4 range selected.

    • for Manual Transaxle:

      The ECM cancels the cruise control system when the clutch pedal is depressed and the ECM receives the clutch pedal stroke sensor signal from electric parking brake ECU.

  2. LIMIT CONTROL


    1. Low speed limit

      The lowest possible limit of the speed setting range is set at approximately 40 km/h (25 mph). The cruise control system cannot be set when the driving vehicle speed is below the low speed limit. The cruise control operation will be automatically canceled but the stored vehicle speed will be retained when the vehicle speed decreases below the low speed limit of 40 km/h (25 mph) while the cruise control is in operation.

    2. High speed limit

      The highest possible limit of the speed setting range is set at approximately 200 km/h (125 mph). The cruise control system cannot be set when the driving vehicle speed is over the high speed limit. Also, +RES cannot be used to increase speed beyond the high speed limit.

  3. OPERATION OF CRUISE CONTROL

    The cruise control switch is used to operate 7 functions: SET, COAST, TAP-DOWN, RES (RESUME), ACCELERATION, TAP-UP, and CANCEL. The SET, TAP-DOWN and COAST functions, and the RES (RESUME), TAP-UP and ACCELERATION functions are operated with the same switch. The cruise control switch is an automatic return type switch which turns on only while holding it in each direction and turns off after releasing it.


    1. SET CONTROL

      The vehicle speed is stored and constant speed control is initiated when pushing the switch to -SET while driving with the cruise control switch on (the CRUISE main indicator light is on), and with the vehicle speed within the set speed range (between the low and high speed limits).

    2. COAST CONTROL

      When the cruise control switch is pushed to -SET and held in that position while the cruise control system is operating, the ECM sends a throttle valve opening angle 0° demand signal to the throttle body. Then, the vehicle speed is stored and maintained when the cruise control switch is released.

      Tech Tips

      An actual throttle valve opening angle of 0° is not possible due to the idle speed control, etc.

    3. TAP-DOWN CONTROL

      When tapping down the cruise control switch to -SET (for approximately 0.6 seconds) while the cruise control system is in operation, the stored vehicle speed decreases each time by approximately 1.6 km/h (1.0 mph). However, when the difference between the driving and stored vehicle speeds is more than approximately 5 km/h (3 mph), the stored vehicle speed is set to the actual vehicle speed at the moment the cruise control switch is released from -SET and constant speed control is initiated.

    4. ACCELERATION CONTROL

      The throttle motor of the throttle body is instructed by the ECM to open the throttle valve when the cruise control switch is pushed to +RES and held while the cruise control system is in operation. When the cruise control switch is released from +RES, the vehicle speed is stored and the vehicle is controlled at a constant speed.

    5. TAP-UP CONTROL

      When tapping up the cruise control switch to +RES (for approximately 0.6 seconds) while the cruise control system is in operation, the stored vehicle speed increases each time by approximately 1.6 km/h (1.0 mph). However, when the difference between the driving and the stored vehicle speed is more than approximately 5 km/h (3 mph), the stored vehicle speed will not be changed.

    6. RES (RESUME) CONTROL

      If cruise control operation was canceled with the stop light switch or the CANCEL switch, and if the driving speed is within the set speed range, pushing the cruise control switch to +RES restores the vehicle speed memorized at the time of cancellation, and initiates constant speed control.

    7. OVERDRIVE CONTROL (SHIFT DOWN CONTROL)


      • Overdrive may cancel automatically when using cruise control while driving on inclined roads, etc.

      • After overdrive is canceled, if the system determines that the road is no longer inclined based on the throttle valve opening amount, overdrive will be restored.

      • If overdrive was canceled during ACCEL or RESUME operation, overdrive will be restored after the ACCEL or RESUME operation is completed.

    8. MANUAL CANCEL CONTROL

      Performing any of the following cancels the cruise control system while in operation (the stored vehicle speed in the ECM is maintained).


      • Depressing the brake pedal

      • Pulling the cruise control switch to CANCEL

      • Driving the vehicle while the vehicle stability control system is operating

      • Turning the cruise control switch off (the stored vehicle speed in the ECM is not maintained)

      • for CVT:

        Moving the shift lever to any position except D or S with the S4 range selected

      • for Manual Transaxle:

        Depressing the clutch pedal

  4. AUTO CANCEL (FAIL-SAFE)

    This system has an automatic cancellation function (fail-safe) Click here.