STOP AND START


  1. FUNCTION OF MAIN COMPONENTS

    Component Function
    Engine Stop and Start ECU Sends either an engine stop or restart signal to the ECM according to the signals from each sensor and switch.
    Engine Stop and Start ECU (Backup Boost Converter) Supplies battery voltage to help make up for the voltage drop that occurs when the engine is restarted, preventing the operation of various systems from being interrupted due to low battery voltage.
    Clutch Upper Switch (Clutch Start Switch Assembly) Recognizes that the clutch pedal is not depressed and sends a signal to the engine stop and start ECU.
    Clutch Lower Switch (Clutch Start Switch Assembly) Recognizes that the clutch pedal is depressed and sends a signal to the engine stop and start ECU.
    Neutral Position Switch Recognizes that the shift lever is in N and sends a signal to the engine stop and start ECU.
    Brake Vacuum Pressure Sensor Detects the brake booster vacuum pressure and sends a signal to the engine stop and start ECU.
    Hood Lock Assembly (Engine Hood Courtesy Switch) Detects whether the hood is open or closed and sends a signal to the engine stop and start ECU.
    Front Door Courtesy Light Switch Assembly (Driver) Detects whether the driver door is open or closed and sends a signal to the engine stop and start ECU via the main body ECU (multiplex network body ECU) via CAN communication.
    Front Seat Inner Belt Assembly (Driver) (Front Seat Belt Buckle Switch (Driver)) Detects whether or not the driver's seat belt has been fastened, and sends a signal to the engine stop and start ECU via the main body ECU (multiplex network body ECU) via CAN communication.
    Air Conditioning Amplifier Assembly* Sends an outside temperature signal and A/C switch signal to the engine stop and start ECU.
    Blower Switch Sends a blower operation signal to the engine stop and start ECU.
    Combination Meter Assembly Stop and Start Indicator Light Turns on when the engine is stopped due to stop and start system control.
    Stop and Start Cancel Indicator Light Turns on to inform the driver that the system has been disabled when stop and start system operation is prohibited by the stop and start system cancel switch assembly.
    If a system malfunction is detected, the stop and start cancel indicator light blinks to inform the driver.
    Multi-information Display (ECO Time and ECO Odometer) Displays the total amount of engine stoppage time occurring since the last reset.
    Ecorun Cancel Switch Assembly Operation of the system can be canceled by pressing the ecorun cancel switch assembly. Pressing the switch again or turning the power source off and back on restores the operation of the system.
    ECM Sends various information about engine conditions to the engine stop and start ECU.
    Brake Actuator Assembly (Skid Control ECU) Sends a vehicle speed signal to the engine stop and start ECU.
    Airbag Sensor Assembly Sends airbag deployment information in the event of a collision and a deceleration signal to the engine stop and start ECU.
    Main Body ECU (Multiplex Network Body ECU) Sends a front door courtesy light switch signal and front seat belt buckle switch (driver) signal to the engine stop and start ECU.
    Power Steering ECU Assembly Sends an electrical power steering assist signal to the engine stop and start ECU.

    *: Models with air conditioning system

  2. SYSTEM CONTROL


    1. Operating Conditions at Engine Stop and Restart


      1. The engine may stop if all of these conditions are detected.

        Item Operating Condition
        Idle Stop Engine Coolant Temperature A predetermined temperature*1 to 105°C (221°F)
        Outside Temperature -5°C (23°F) or more
        Driver Door Closed
        Brake Booster Vacuum Sufficient brake booster vacuum
        Ecorun Cancel Switch Assembly Off condition
        Vehicle Speed 0 km/h (0 mph)
        Clutch Pedal Released
        Shift Lever Position Neutral
        Engine Hood Closed
        Battery Voltage Minimum input voltage to the starter is 7.6 V or more, and minimum voltage is 8.14 V or more at cranking after going into the starter
        Battery Temperature -10°C to 70°C (14°F to 158°F)
        Battery Integrated Current*2

        1. 0 A-sec or more: After engine start by ignition switch operation

        2. After the integrated current value has increased to 0 A-sec or more at least once after ignition switch is turned to ON:


          • More than -4834 A-sec: When the battery is sufficient and the battery temperature is -1°C (30°F) or more, or lower than 70°C (158°F).

          • More than -864 A-sec: When the battery is low and the battery temperature is less than -1°C (30°F), or 70°C (158°F) or more.
        Air Conditioning*3 Off or on with an outside temperature of 25°C (77°F) or lower and an evaporator temperature of 9°C (48°F) or lower.
        Heater Off or on with an outside temperature of 10°C (50°F) or higher and an engine coolant temperature of 45°C (113°F) or higher.

        *1: The lowest operating temperature is determined by environmental conditions.

        *2: Regarding Battery Integrated Current

        In the stop and start system, the engine stop and start ECU switches the system control mode (stop and start system control permitted/prohibited) based on the battery condition (charge/discharge condition) to protect the battery and to ensure stable engine restarting performance.

        The battery charge-discharge condition is determined from the integrated current value calculated from the battery current sensor signal. The integrated current value is obtained by multiplying the current (ampere) detected by the battery current sensor by the time (seconds), and it is expressed in the unit A-sec. This can be measured by Global TechStream (GTS).

        The engine stop and start ECU determines the power charge based on the integrated current value and prohibits stop and start system control if the value is below the threshold, because the battery might not be able to start the engine. The threshold varies according to the battery temperature and battery charge condition.

        *3: Models with air conditioning system

      2. The engine will restart if any of these conditions are detected.

        Item Operating Condition
        Engine Restart Brake Booster Vacuum Insufficient brake booster vacuum
        Air Conditioning*1 The timer in the air conditioning amplifier assembly operates when the air conditioning is on.
        Heater When the automatic blower function is operating, the timer in the air conditioning amplifier assembly operates. Otherwise, the timer in the engine stop and start ECU operates.
        Air Conditioning*1 / Heater The A/C switch (air conditioning control assembly), blower switch (air conditioning control assembly), rear window defogger or mirror heater switch*3 is turned on.
        Ecorun Cancel Switch Assembly The ecorun cancel switch assembly is turned on.
        Heater Switch Assembly*2 The heater switch assembly is turned on.
        Battery Low battery performance or low battery voltage
        Engine Hood The engine hood is open, the shift lever is in N and the clutch pedal is released.
        Driver's Door The driver's door is opened.
        Driver's Seat Belt The driver's seat belt is unfastened.
        Vehicle Speed A vehicle speed signal is input.
        Clutch Pedal The clutch pedal is depressed.
        DPF Warning Indicator Light Illuminates.

        *1: Models with air conditioning system

        *2: Models with combustion type power heater

        *3: Models with automatic air conditioning system

    2. System Prohibit Control


      1. For safety, battery protection, comfort and ECU learning reasons, the engine stop and start ECU prohibits stop and start system operation if any one of the following conditions is met.

        Prohibition Reason Condition
        Safety If the engine is started with the hood open, such as when jump starting, engine restart operation cannot be ensured. Therefore, stop and start system operation will be prohibited. The operation of the system will be restored on the next trip.
        If the driver door or hood is opened before the engine stops, stop and start system operation will be prohibited for safety reasons.
        The brake booster vacuum is insufficient.
        If the air conditioning is on when the outside temperature is low, stop and start system operation will be prohibited.*1
        If the engine stop and start ECU receives an airbag deployment signal in the event of a collision, stop and start system operation will be prohibited for safety reasons.
        If the driver's seat belt is unfastened before the engine stops
        Battery Protection If the electrical load is high and the engine is stopped for a long period of time, stop and start system operation will be prohibited.
        A refresh charge is performed every time the vehicle is driven for a total of 20 hours. During the refresh charge, which takes 30 minutes to 1 hour, stop and start system operation will be prohibited.
        If the amount of time the engine has been stopped exceeds 40%, stop and start system operation will be prohibited. The economical driving percentage is calculated by dividing engine stop time by ignition switch ON time.

        1. If the battery integrated current is less than 0 A-sec after engine start by ignition switch operation, stop and start system operation will be prohibited.

        2. After the integrated current value increases to 0 A-sec or more once:


          • More than -4834 A-sec: When the battery is sufficient and the battery temperature is -1°C (30°F) or more, or lower than 70°C (158°F).

          • More than -864 A-sec: When the battery is low and the battery temperature is less than -1°C (30°F), or 70°C (158°F) or more.
        Comfort If the air conditioning is on when the outside temperature is high and the evaporator temperature is high, stop and start system operation will be prohibited.*1
        If the heater is on when the outside temperature is low and the engine coolant temperature is low, stop and start system operation will be prohibited.
        If the front DEF switch (air conditioning control assembly) and blower switch (air conditioning control assembly) are on, stop and start system operation will be prohibited.
        If the heater switch assembly*2 is turned on, stop and start system operation will be prohibited.
        Engine Protection DPF regeneration is prior to stop and start operation during DPF regeneration.

        *1: Models with air conditioning system

        *2: Models with combustion type power heater

    3. Warning Control


      1. If any of the following operations are performed while the engine is stopped due to system control, the system will not restart the engine. The driver will be warned by a buzzer, or the engine will be regarded as stalled or will be restarted.

        Operation Warning Control
        Driver door is opened. The engine changes to 'stalled' or restarted.
        Hood is opened. The engine changes to 'stalled' or restarted.
        Shift lever is moved without depressing the clutch pedal. Buzzer sounds.

  3. DIAGNOSIS


    1. When the engine stop and start ECU detects a malfunction and CAN communication is normal, the engine stop and start ECU records information related to the malfunction. Furthermore, the stop and start indicator light in the combination meter assembly blinks to inform the driver that CAN communication is normal.

    2. The engine stop and start ECU also stores Diagnostic Trouble Code (DTCs) related to malfunctions. DTCs can be read using the Global TechStream (GTS).