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)*1 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)*1 Recognizes that the clutch pedal is depressed and sends a signal to the engine stop and start ECU.
    Park/Neutral Position Switch Assembly*2 Detects whether the shift lever position is in park/neutral 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*3 Sends an outside temperature signal and an engine restart 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.

    • Inform the driver by sounding the buzzer and blinking the stop and start indicator, of the shift lever being in any position other than N without the clutch pedal depressed. (Changing the shift lever to N will stop sounding the buzzer and flushing the indicator light.)*1
    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 occers and operation frequency of the starter assembly is over the threshold, the stop and start cancel indicator light blinks to inform the driver.
    Multi-information Display

    • Displays the current idling stop time, the idling stop time since the ignition switch was turned from ON to off, and the total idling stop time since the last time the idling stop was reset.

    • Displays the settings of the stop and start system or warning information, etc.
    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.
    Electric Oil Pump for CVT*2 Holds the CVT oil pressure during idle stop.
    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.
    Stop Light Switch Assembly*2 Detects a brake pedal released condition and sends a signal to the engine stop and start ECU via the ECM.
    Battery Sensor (Battery State Sensor Assembly) Detects the battery charging and discharging amount and sends a signal to the engine stop and start ECU via the ECM.
    Accelerator Pedal Sensor Assembly*2 Detects an accelerator pedal opening angle and sends a signal to the engine stop and start ECU via the ECM.
    Transmission Valve Body Assembly*2 CVT Fluid Temperature Sensor Detects the CVT fluid temperature.
    Engine Coolant Temperature Sensor Sends the coolant temperature to the engine stop and start ECU via the ECM.
    Generator Assembly Sends the generator assembly generation condition to the engine stop and start ECU via the ECM.

    *1: Models with manual transaxle

    *2: Models with multidrive/continuously variable transaxle

    *3: Models with air conditioning system

  2. SYSTEM CONTROL


    1. Early Stage Injection Control (Models with Multidrive/Continuously Variable Transaxle)


      1. Early stage injection control shortens the time it takes the engine to restart after the stop and start system stops the engine, thus allowing smooth initial acceleration.

      2. The ECM memorizes the crankshaft angle detected by the crank position sensor when the engine is stopped by the stop and start system.

      3. The ECM judges the injection required and decides which cylinder to ignite when the driver does restart operation. The ECM then uses this information as it starts the engine.

        A01T119E03

    2. Hill-start Assist Function (Models with Multidrive/Continuously Variable Transaxle)


      1. The driving force (creep phenomenon) of a former CVT vehicle is regulated by depressing the brake pedal while stopped, and the driving force is transmitted by releasing the brake pedal when starting the vehicle. However, when starting a stop and start system equipped vehicle with its engine stopped due to the activation of the idle stop function, there is a short time delay before the driving force is generated as the engine will start after the brake pedal is released.

      2. The hill-start assist function is a system to assist starting of a stop and start system equipped vehicle on a slope to deal with the situation described above, retaining the brake hydraulic pressure until sufficient driving force is generated.

    3. 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 40°C to 105°C (104°F to 221°F)
        CVT Oil Temperature*1 25°C to 111°C (77°F to 231.8°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*2 Released
        Shift Lever Position*1 P, N, D, M
        Shift Lever Position*2 Neutral
        Engine Hood Closed
        Battery Voltage 6.5 V or more at engine start.
        Battery Temperature -10°C to 70°C (14°F to 158°F)*3
        Battery Integrated Current*4

        When the integrated current value meets any of the following conditions:


        • -3974 A-sec or more: Status of Battery Charge Control is Charge Control Coordination Mode or Low Temperature Mode.*5

        • 0 A-sec or more: Status of Battery Charge Control is Stop and Start Standalone Mode, Stop and Start Restriction Mode or Temperature High/Low Mode.*6
        Air Conditioning*7 During "cooling down or warming up" or defrost function is not operating.
        Steering Operation Not operated
        Engine Speed 1250 r/min or less
        Driver's Seat Belt 3 seconds or more elapse after the seat belt is fastened.
        Accelerator Pedal Not depressed
        Road Gradient*1 -8° to 8°

        *1: Models with multidrive/continuously variable transaxle

        *2: Models with manual transaxle

        *3: When the battery temperature becomes -15°C or lower or 75°C or higher, control is prohibited. After control is prohibited and the battery temperature rises to -10°C or higher or falls to 70°C or lower, control is performed.

        *4: 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 sensor (battery state sensor assembly) signal. The integrated current value is obtained by multiplying the current (ampere) detected by the battery sensor (battery state sensor assembly) by the time (seconds), and it is expressed in the unit A-sec. This can be measured by the 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.

        *5: After the integrated current value becomes -4838 A-sec or less, in order to charge the battery, control is prohibited until the value becomes -3974 A-sec or more.

        *6: After the integrated current value becomes -864 A-sec or less, in order to charge the battery, control is prohibited until the value becomes 0 A-sec or more.

        *7: 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/Heater

        • When the air conditioning is on and a timer in the air conditioning amplifier assembly completes.*1

        • The A/C switch*1, blower switch, rear window defogger switch or mirror heater switch*2 is turned on.

        • Evaporator temperature exceeds threshold (threshold varies with temperature, humidity and amount of solar radiator)
        Ecorun Cancel Switch Assembly The ecorun cancel switch assembly is turned on.
        Battery

        • The battery voltage is less than 11.4 V.

        • The battery integrated current drops to below the threshold value.
        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.
        Brake Pedal*3 The brake pedal is released.
        Shift Lever*3

        • Moved from D or M position to R position.

        • Moved from P or N position to another position.
        Clutch Pedal*4 The clutch pedal is depressed.
        Steering Operation The steering wheel is operated.

        *1: Models with air conditioning system

        *2: Models with mirror heater system

        *3: Models with multidrive/continuously variable transaxle

        *4: Models with manual transaxle

    4. 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. 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.
        The brake booster vacuum is insufficient.
        The driver seat belt is unfastened before the engine stops.
        The engine catalyst is being quickly warmed up.
        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.
        The refresh charge continues for 0.5 to 1 hour, and is carried out approximately every about 20 hours or driving. While refresh charge, stop and start system operation will be disabled.
        When the idle stop rate becomes higher than a predetermined rate, stop and start system operation will be disabled.
        When the battery voltage becomes low and the battery integrated current value drops to below the threshold value, stop and start operation will be disabled.
        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.*
        If the air conditioning is on when the outside temperature is low, stop and start system operation will be prohibited.*
        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 and blower switch are on, stop and start system operation will be prohibited.

        *: Models with air conditioning system

    5. 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 status changes to 'stalled' or is restarted.
        Hood is opened. The engine status changes to 'stalled' or is restarted.
        Shift lever is moved without depressing the clutch pedal.* Buzzer sounds and the stop and start indicator light blinks.
        The driver seat belt is released. The engine changes to restarted.

        *: Models with manual transaxle

  3. FUNCTION


    1. Settings of Stop and Start System


      1. Using the steering pad switch assembly and the multi-information display on the combination meter assembly, the engine stop operation time due to stop and start control when the air conditioning system is on can be changed between Normal and Extended (the stop and start system has priority).

  4. 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).