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System Description [11/2021 - 08/2023]

  1. STOP AND START CONTROL 

    The stop and start system operates according to the following conditions, achieving appropriate engine stop and start control together with safe and smooth driving characteristics.

    1. When all of the conditions in the following table have been met, the engine is stopped by stop and start control.
      Item Condition
      (All of the following conditions are met)
      Idle Stop Push Start Switch Assembly More than 5 seconds elapsed at ON
      Engine Coolant Temperature 70 to 100°C (158 to 212°F)
      Ambient Temperature -5°C (23°F) or higher
      Driver Door 3 seconds have elapsed after driver door closed
      Driver Seat Belt Driver side buckle is latched
      Brake Booster Vacuum On a flat place, more than 1 second elapses at more than 42.5 kPa (Threshold values change according to road surface gradient and brake master pressure.)
      Brake Master Cylinder Fluid Pressure*1 1.6 MPa or higher (16.3 kgf/cm2 , 232 psi) (changes according to gradient)
      Shift Position After shift lever is operated and 1 second elapses, shift lever is in D
      Drive Mode NORMAL, ECO, COMFORT or SPORT mode
      Transfer 2H mode
      Automatic Transmission Fluid Temperature
      • 20 to 110°C (68 to 230°F)
      • Other than when stop and start control is prohibited due to insufficient automatic transmission fluid pressure, etc.
      Stop and Start System Cancel Switch (Eco Run Cancel Switch Assembly) OFF
      Vehicle Speed 0 km/h (0 mph) (After the engine has warmed up and is running)
      Road Grade Road Surface Gradient: Road Surface gradient condition is permitted (road surface gradient is within -1.02m/s2 to 1.36 m/s2 )
      Engine Speed 1250 rpm or less (changes according to engine coolant temperature)
      Hood 3 seconds have elapsed after hood closed
      Battery Voltage*2 When using specified battery: 
      1. 8.3 V or higher when starter begins operation and 8.3 V or higher when cranking

      When using non-specified battery: 

      1. 8.92 V or higher when starter begins operation and 8.92 V or higher when cranking
      Battery Fluid Temperature*3 -10°C or higher and 55°C or less (14°F or higher and 131°F or less)
      Battery Integrated Current*4 One of the following conditions is met: 
      • -17971 A-sec or more: "Status of Battery Charge Control"*4 is Charge Control Coordination Mode, Stop and Start Standalone Mode, Temperature High/Low Mode or Low Temperature Mode
      • 0 A-sec or more: "Status of Battery Charge Control"*4 is Stop and Start Restriction Mode
      Battery Charge Control*5 The value of Data List item Status of Battery Charge Control*4 is Charge Control Coordination Mode, Stop and Start Standalone Mode, Stop and Start Restriction Mode, Temperature High/Low Mode or Low Temperature Mode
      Idling Stop Rate /
      Total Idling Stop Rate
      • Idling stop rate for one trip: 50% or less (Varies according to battery fluid temperature).
      • Total idling stop rate: Less than 40%

      HINT: 

      • Idling stop rate: Idling stop rate for ignition on time (1 trip)
      • Total idling stop rate: Idling stop rate for total ignition on time
      Air Conditioning Any of the following conditions are met: 
      • Defogger Switch: OFF, and Blower Switch: OFF
      • With blower switch on, evaporator temperature below threshold (varies depending on each temperature, humidity, amount of solar radiation, etc.) and after certain period of time since engine restarted by stop and start system (threshold varies depending on idling stop conditions)
      Heater One of the following conditions is met: 
      • Blower switch is off
      • While blower switch is on and A/C switch is off, one of the following conditions is met:
        • Ambient temperature is higher than 10°C, or
        • Engine coolant temperature is higher than 55°C, or
        • Vehicle cabin temperature is higher than the set temperature - 5°C
      • While blower switch is on and A/C switch is off, a certain amount of time has elapsed after engine state changed from "not running" to "running".
      Cooler One of the following conditions is met: 
      • Blower switch is off
      • A/C switch is off
      • Ambient temperature 23°C (73°F) or less
      • Evaporator internal temperature less than 9°C (48°F), air mix damper opening value more than 10%, and vehicle cabin temperature less than 3°C (37°F) above set temperature or blower level less than 16 (when ignition switch turned to ON for first time in one trip)
      Engine Control
      Steering Wheel When the steerage angle of the steering wheel is 45 degrees or less.
      Dynamic Radar Cruise Control System
      • When the dynamic radar cruise control (w/ Full Speed Range Following Function) system is operating and the brake hold function is operating, the preceding vehicle starts off or the user performs a resume operation (starts off the vehicle).
      • When the condition is prohibited by radar cruise control

      HINT: 

      • *1: Enough brake force is applied to prevent the vehicle from moving when the engine is started again.
      • *2: If stop and start control is prohibited (NG) due to battery voltage, stop and start control will begin operating again (OK) when one of the following conditions is met
        • When the engine is started and the battery voltage permission conditions are met after the ignition switch is turned off and 8 hours have elapsed
        • When the battery voltage permission conditions are met after "Starter (Hood Closed)" is performed using the GTS
      • *3: When the battery fluid temperature is -15°C (5°F) or less, or 60°C (140°F) or higher, stop and start control is prohibited. When the battery fluid temperature returns to -10°C (14°F) or higher, and 55°C (131°F) or less, stop and start control is permitted.
      • *4: Read the Data List items "Integrated Current" and "Stop&Start Operating Permission (Integrated Current)" when checking the integrated current value.

        Refer to DATA LIST / ACTIVE TEST [11/2021 - 08/2023] 

      • *5: Please refer to the Data List "Status of Battery Charge Control" for information about the status of the battery charge control.
    2. When the engine is stopped by stop and start control, and any of the following conditions are met, the engine will restart.
      Item Condition
      (Any of the following conditions is met)
      Engine Restart Brake Booster Vacuum Brake booster vacuum insufficient (Under 37.5 kPa (0.38 kg/cm2 , 5.4 psi)) (Brake booster vacuum changes in accordance with brake fluid pressure (brake pedal effort))
      Engine control System Malfunction in engine control system is detected
      Automatic Transmission Fluid Temperature Temperature is less than 20°C (68°F) or more than 110°C (230°F)
      Power Steering System Malfunction in power steering system is detected
      Electronically Controlled Brake System Malfunction in electronically controlled brake system is detected
      Oil Pump Assembly with Motor Oil pump assembly with motor malfunctioning
      Air Conditioning Timer in the air conditioning amplifier assembly runs out
      Heater Timer in the air conditioning amplifier assembly runs out
      Air Conditioning/Heater Both of the following conditions are met: 
      • Blower switch: ON
      • Evaporator temperature exceeds threshold value (threshold value varies with temperature, humidity and amount of solar radiation)

      Any of the following conditions are met: from OFF to ON 

      • A/C switch, blower switch: from OFF to ON
      • Defogger switch: from OFF to ON
      • During blower OFF and Auto control, when it changed to manual blower
      • Changes from stop and start system priority control to normal system control
      Battery Battery voltage drops (11.8 V or less)
      Battery Integrated Current* The accumulated value of discharge current during engine stop is too large (3456 A-sec or more)
      Vehicle Speed Vehicle speed signal is input (Vehicle stopped on a slope, etc.)
      Drive Mode Except NORMAL, ECO, COMFORT or SPORT mode
      Transfer Transfer position 2H to 4H/4L
      Driver Door Open
      Driver Seat Belt Driver seat belt is unfastened
      Steering Wheel Steering wheel turned 25 degrees or more
      Brake Pedal Brake pedal released
      Accelerator Pedal Accelerator pedal is depressed
      Shift Position Shift lever moved from D or P to other position
      Stop and Start System Cancel Switch (Eco Run Cancel Switch Assembly) When stop and start system cancel switch (eco run cancel switch assembly) is turned from off to on
      Dynamic Radar Cruise Control System When the dynamic radar cruise control (w/ Full Speed Range Following Function) system is operating and the brake hold function is operating, the preceding vehicle starts off or the user performs a resume operation (starts off the vehicle).

      HINT: 

      1. *: Read the Data List items "Integrated Current" and "Stop&Start Operating Permission (Integrated Current)" when checking the integrated current value

        Refer to DATA LIST / ACTIVE TEST [11/2021 - 08/2023] 

  2. WARNING CONTROL 

    If any of the following operations are performed while the engine is stopped due to stop and start control, the system will not restart the engine. The engine will change the mode from "stopped due to system control" to "stalled" or the driver will be warned using the buzzer.

    Operation Warning Control
    The engine hood is opened with the shift lever in D The engine stops (mode changes to "stalled", and the engine cannot be restarted until the ignition switch is turned off and then to ON)
    The driver door is opened with the shift lever in D The engine starts, warning buzzer sounds and stop and start indicator blinks
    The driver seat belt is unfastened The engine starts
  3. WARNING INDICATOR AND BUZZER OPERATION 

    The driver is informed of the system control status and warnings by the stop and start indicator, stop and start cancel indicator and the buzzer.

    HINT: 

    The stop and start indicator and the stop and start cancel indicator are displayed at the same location in the combination meter.

    One or the other will be displayed according to the order of priority, but they will not be illuminated simultaneously.

    STOP AND START INDICATOR AND BUZZER OPERATION

    Item Condition Stop and Start Indicator Stop and Start Cancel Indicator Buzzer
    For 3 seconds after the ignition switch to ON Normal operation Comes on Comes on Does not sound
    During stop and start control operation (engine is stopped) Normal operation Comes on Does not come on Does not sound
    Driver door opened The blinking interval 0.15 seconds* Does not come on Sounds*
    After engine started by stop and start control Driver door opened within 5 seconds of engine start The blinking interval 0.15 seconds* Does not come on Sounds*
    Control is prohibited by the stop and start system cancel switch (eco run cancel switch assembly) Normal operation Does not come on Comes on Does not sound
    Diagnostic trouble code Any DTCs are stored Does not come on The blinking interval 0.5 seconds Does not sound
    Starter assembly life Number of times the starter has been operated exceeds its limit Does not come on The blinking interval 0.5 seconds Does not sound
    Drive plate and ring gear sub-assembly life Number of times the engine start has been operated exceeds its limit Does not come on The blinking interval 0.5 seconds Does not sound
    GTY694329Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *a Stop and Start Indicator
    *b Stop and Start Cancel Indicator
    1. *: Shift lever in D
  4. MULTI-INFORMATION DISPLAY MESSAGE AND INDICATOR OPERATION 

    An indicator and/or messages are displayed on the multi-information display to indicate the condition of the stop and start system when certain vehicle conditions are met.

    Stop and Start System Condition Multi-information Display Message*1 Vehicle Condition
    When the engine cannot be stopped by the stop and start system
    *2
    "Press Brake More to Activate" The brake pedal is not depressed enough.
    "Non-Dedicated Battery" A non-specified battery for the stop and start system may have been installed.
    "Battery Charging"
    • The battery charge amount may be low.
    • The battery voltage is low
    • The battery fluid temperature is high
    • A refresh charge may be occurring.
    "Stop & Start system Unavailable"
    • The engine may have been started with the hood opened.
    • The stop and start system is temporarily disabled.
    "In Preparation"
    • The vehicle is being driven in a high altitude area.
    • The brake booster vacuum is low.
    "For Climate Control"
    • The air conditioning system is being used when the ambient temperature is high or low.
    • Windshield defogger is pressed.
    When the engine automatically restarts while stopped by the stop and start system
    *2
    "In Preparation" The brake pedal is strongly depressed further or pumped.
    "For Climate Control"
    • The air conditioning system is turned on or the air conditioning is being used.
    • Windshield defogger is turned on.
    "Battery Charging" The battery charge amount may be low.
    The system may be malfunctioning - "Stop & Start System Malfunction Visit Your Dealer" -

    HINT: 

    • *1: Messages are listed in the order of priority.
    • *2: When the engine cannot be stopped by the stop and start system or the engine is restarted while the engine is stopped by the stop and start system, the following mark is displayed on the multi-information display.
  5. STOP AND START SYSTEM OPERATION 

    Depending on the type of malfunction, stop and start control may be prohibited by the fail-safe function. The following table shows effects on the vehicle and areas to be inspected when there is a malfunction in the stop and start system.

    Malfunctioning Area Malfunction DTC Output Data List / Freeze Frame Data Effect on Vehicle Area to be Inspected
    IGSW circuit Open P2530-14 IG Switch
    • Stop and start control prohibited
    • Stop and start cancel indicator light blinks
    Wire harness or connector
    +B circuit Open - Data List cannot be checked because power not supplied to the engine stop and start ECU Stop and start control prohibited Wire harness or connector
    CLL (park/neutral position switch assembly) circuit Stuck on P0850-14 Neutral Switch
    • Stop and start control prohibited
    • Stop and start cancel indicator blinks
    • Wire harness or connector
    • Park/Neutral position switch assembly
    Stuck off P0850-12
    • Stop and start control prohibited
    • Stop and start cancel indicator blinks
    BNT1 (engine hood courtesy switch) circuit Stuck on - Hood Courtesy Switch Mode does not change to "stalled" when engine hood opened with shift lever in D and engine stopped by stop and start control
    • Wire harness or connector
    • Hood lock assembly (engine hood courtesy switch)
    Stuck off - Stop and start control prohibited despite engine hood being closed
    ECAN (stop and start system cancel switch (eco run cancel switch assembly)) circuit Stuck on - Stop&Start Cancel Switch Stop and start control prohibited
    • Wire harness or connector
    • Stop and start system cancel switch (eco run cancel switch assembly)
    Stuck off - Stop and start control cannot be canceled by pressing the stop and start system cancel switch (eco run cancel switch assembly)
    BRVC/PB/BRE2 (vacuum sensor) circuit Open P0555-15 Brake Boost Pressure
    • Stop and start control prohibited
    • Stop and start cancel indicator blinks
    • Wire harness or connector
    • Vacuum sensor assembly
    • Brake booster assembly
    • Vacuum hose
    Shorted
    • P0555-11
    • P0555-15
    Remains at intermediate value
    • P0555-00
    • P0555-2A
    NOPM circuit
    OPM1 circuit
    OP21 circuit
    (Automatic transmission oil pump assembly)
    • Open
    • Shorted
    • Internal circuit malfunction
    • P0C2B-11
    • P0C2B-15
    • P2797-96
    • Oil Pump Relay
    • Oil Pump Duty
    • State of Oil Pump Motor Revolution
    • Oil Pump Motor Revolution Frequency
    • Stop and start control prohibited
    • Stop and start cancel indicator blinks
    • Wire harness or connector
    • Engine stop and start ECU
    • Oil pump assembly with motor
    Automatic transmission oil pump assembly with motor Oil pump assembly with motor malfunction P0942-96 Stop&Start Operating Permission (AT/CVT)
    • Stop and start control prohibited
    • Stop and start cancel indicator blinks
    Oil pump assembly with motor
    STA circuit Overcurrent P0615-19 -
    • Stop and start control prohibited
    • Stop and start cancel indicator blinks
    • BBC NO. 1 fuse
    • BBC NO. 2 fuse
    • Wire harness or connector
    • ST relay
    • Engine stop and start ECU
    Stuck on P1644-00
    • Wire harness or connector
    • ST relay
    • Engine stop and start ECU
    Stuck off P1644-00
    BBC (backup boost converter) circuit Overcurrent P323A-19 State of BBC
    • Stop and start control prohibited
    • Stop and start cancel indicator blinks
    • BBC NO. 1 fuse
    • BBC NO. 2 fuse
    • Wire harness or connector
    • Engine stop and start ECU
    • Battery
    • ECUs and sensors connected to B41, B42, B43 and IG41
    • Open
    • Shorted
    • Internal circuit malfunction
    • Battery
    • P30DF-62
    • P30EF-4B
    • P323A-00
    • P323A-16
    • P323A-A2
    • P323B-29
    • P323B-38
    State of BBC
    • Stop and start control prohibited
    • Stop and start cancel indicator blinks
    • BBC NO. 1 fuse
    • BBC NO. 2 fuse
    • Wire harness or connector
    • Engine stop and start ECU
    • Battery
    External backup boost converter (eco run vehicle converter assembly) circuit
    • Open
    • Shorted
    • Internal circuit malfunction
    • Battery
    P33B3-00
    • State of External BBC
    • External BBC Overcurrent History
    • Stop and start control prohibited
    • Stop and start cancel indicator blinks
    • BBC NO. 3 fuse
    • Wire harness or connector
    • External backup boost converter (eco run vehicle converter assembly)
    • Battery
    ECU inner circuit Malfunction P1644-9E -
    • Stop and start control prohibited
    • Stop and start cancel indicator blinks
    Engine stop and start ECU
    Monitoring CPU circuit Malfunction P0606-29 State of BBC
    • Stop and start control prohibited
    • Stop and start cancel indicator blinks
    Engine stop and start ECU
    Crankshaft position sensor circuit Open P0335-62
    • Engine Speed (ECM)
    • Engine Speed
    • Stop and start control prohibited
    • Stop and start cancel indicator blinks
    • Wire harness or connector
    • Crankshaft position sensor
    EFFECTS ON VEHICLE DUE TO RELATED SYSTEM MALFUNCTIONS

    Malfunctioning Area Malfunction DTC / RoB Output Data List / Freeze Frame Data Effect on Vehicle Area to be Inspected
    Engine control system MIL illuminated DTCs for engine control system output
    • Stop&Start Operating Permission (ECM 1)
    • Stop&Start Operating Permission (ECM 2)
    Stop and start control prohibited Engine control system
    Abnormal NE signal DTCs for engine control system output -
    • Stop and start control prohibited
    • Stop and start cancel indicator blinks
    • Engine control system (crankshaft position sensor circuit)
    • Wire harness or connector
    Crankshaft reverse rotation detection DTCs for engine control system output -
    • Stop and start control prohibited
    • MIL illuminated
    Engine control system (crankshaft position sensor circuit)
    Charging system Battery state sensor assembly malfunction Charging system DTCs output
    • Battery Fluid Temperature
    • Integrated Current
    Stop and start control prohibited Charging system
    Electronically controlled brake system ABS running - ABS Running Stop and start control prohibited -
    Malfunction in wheel speed sensor Brake control system DTCs output
    • Vehicle Speed
    • Wheel Speed Malfunction
    Stop and start control prohibited
    • Wire harness or connector
    • Skid control ECU (Brake actuator assembly)
    • Vehicle speed sensor
    Seat belt warning system Malfunction in seat belt warning system - Driver Seat Belt Buckle Switch
    • Stop and start control prohibited (stuck off)
    • Engine does not restart when it is stopped by stop and start control (stuck on)
    • Front seat inner belt assembly (for driver side)
    • Wire harness or connector
    Driver door courtesy light switch circuit Malfunction in driver door courtesy light switch circuit - Driver Courtesy Switch Signal
    • Stop and start control prohibited (stuck off)
    • Engine does not restart when it is stopped by stop and start control (stuck on)
    • Stop and start indicator blinks
    • Sounds the warning buzzer
    • Front door courtesy light switch assembly (for driver side)
    • Driver door courtesy light switch circuit
    Air conditioning system Malfunction in ambient temperature sensor Air conditioning system DTCs output Ambient Temperature Stop and start control prohibited Ambient temperature sensor circuit
    Brake vacuum Brake booster vacuum drops -
    • Brake Boost Pressure
    • Brake Negative Pressure
    Stop and start control prohibited
    • Brake booster assembly vacuum
    • Brake booster assembly
    • Vacuum sensor assembly
    • Vacuum hose
    Power source Backup boost converter malfunction
    • P30DF-62
    • P30EF-4B
    • P323A-00
    • P323A-16
    • P323A-A2
    • P323B-29
    • P323B-38
    State of BBC
    • Stop and start control prohibited
    • Stop and start cancel indicator blinks
    • BBC NO. 1 fuse
    • BBC NO. 2 fuse
    • Wire harness or connector
    • Engine stop and start ECU
    • Battery
    Charging system malfunction - Alternator Status Stop and start control prohibited Charging system
    Charging control system X0879 -
    • Stop and start control prohibited
    • Stop and start cancel indicator blinks
    Charging system
    Number of starter operations Exceeds the specified limit X0877
    • Starter Operation #
    • Number of Engine Starts (IG-ON)
    • Number of Engine Starts (Stop & Start)
    • Stop and start control prohibited
    • Stop and start cancel indicator blinks
    • Starter assembly replacement is required
    • ST relay replacement is required
    • Fuse replacement is required
    Usage limit for starting related parts Drive plate and ring gear sub-assembly usage limit X0878 Total Number of Engine Starts
    • Stop and start control prohibited
    • Stop and start cancel indicator blinks
    Drive plate and ring gear sub-assembly replacement is required
    Starter signal malfunction Signal does not match with the starter switch P0615-62
    • Starter
    • Engine Starter Signal
    • Stop and start control prohibited
    • Stop and start cancel indicator blinks
    • Wire harness or connector
    • Engine stop and start ECU
    Jump start Engine started with the engine hood open - Stop&Start Operating Prohibition (Jump Start) Stop and start control prohibited
    (permitted when the ignition switch is turned off)
    • Check for history of roadside service or jump start due to dead battery
    • Hood lock assembly (engine hood courtesy switch)
    CAN communication Communication interrupted
    • U0100-87
    • U0101-87
    • U0114-87
    • U0126-87
    • U0129-87
    • U0140-87
    • U0151-87
    • U0155-87
    • U0164-87
    • U1110-87
    • U114C-87
    • U1170-87
    -
    • Stop and start control prohibited
    • Stop and start cancel indicator blinks
    • Applicable wire harness or connector
    • Applicable ECU