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Precaution [11/2023 - ]

  1. PRECAUTIONS WHEN INSPECTING STOP AND START SYSTEM 
    NOTE:

    When the audio and visual system volume is high, a fail-safe function may operate in order to maintain the operation of stop and start control. The fail-safe function is canceled when the ignition switch is turned off. Using the same power source for the audio and visual system and other systems allows the fail-safe functions to operate more precisely.

  2. WHEN THE ENGINE STOP AND START ECU, OIL PUMP WITH SOLENOID ASSEMBLY AND THE STARTER ASSEMBLY ARE REPLACED 
    NOTE:
    • When the engine stop and start ECU is replaced, it is necessary to read the number of starter operations before replacement, and to store this number in the new engine stop and start ECU, and perform external backup boost converter (eco run vehicle converter assembly) existence learning. Moreover, initialization/learning of the deceleration sensor zero point and checking the operation of oil pump with solenoid assembly are also required.

      Refer to REGISTRATION [11/2023 - ] 

    • When the starter assembly is replaced, the number of starter operations stored in the engine stop and start ECU must be reset.

      Refer to REGISTRATION [11/2023 - ] 

    • When the starter assembly is replaced, "ST relay" must be also replaced.
    • When the oil pump with solenoid assembly or engine stop and start ECU is replaced, check the oil pump with solenoid assembly.

      Refer to REGISTRATION [11/2023 - ] 

    • When the engine stop and start ECU has been replaced, perform ECU security key registration.

      Refer to UPDATE ECU SECURITY KEY [11/2023 - ]

  3. PRECAUTIONS WHEN BATTERY IS DISCHARGED AFTER LEAVING VEHICLE FOR A LONG TIME 

    HINT: 

    If the vehicle has not been driven for a long time, the battery charge will be low and stop and start control operation will be prohibited. If the integrated current value does not exceed the threshold*1 even though the battery has been charged until the charging current decreases to 5 A or less, perform an integrated current value initialization*2 and drive the vehicle for approximately 5 to 40 minutes until the stop and start system operates.

    *1: Refer to System Description for details on the integrated current threshold.

    Refer to SYSTEM DESCRIPTION [11/2023 - ] 

    *2: Use the GTS to perform Integrated Current Value Initialization.

    Refer to REGISTRATION [11/2023 - ] 

  4. PRECAUTIONS WHEN CONNECTING/DISCONNECTING CABLE TO/FROM NEGATIVE BATTERY TERMINAL 
    NOTE:

    To prevent the key from being locked in the vehicle, make sure to enter e-latch inspection mode and enable the manual release handle before disconnecting the cable from the negative (-) battery terminal.

    Refer to INSPECTION MODE PROCEDURE [12/2019 - ]

    HINT: 

    • If the cable is disconnected from the battery terminal, stop and start control is prohibited until refresh charge is completed.

      In this case, let the vehicle idle to complete the refresh charge. The refresh charge is complete when the Data List item Status of Battery Charge Control changes from "Refresh Charge Mode". (Usually, idling the engine for 5 to 60 minutes with the battery fluid temperature at 11°C (52°F) or higher, the refresh charge will be completed.)

    • If the GTS is not available and the Data List item Status of Battery Charge Control cannot be checked, charge the battery by idling the engine for approximately 5 to 60 minutes or driving the vehicle, and then drive the vehicle and check that stop and start control operates.

      If the engine is started with the hood open, the system determines that a jump start has occurred. Therefore, make sure that the hood is closed before starting the engine and driving the vehicle.

    • After the refresh charge completes, turn the ignition switch off, wait for at least 30 seconds, and then start the engine again. If the vehicle enters refresh charge mode again while the engine is idling, the initial refresh charge did not properly complete, so wait for the refresh charge to complete.
    1. If power is not supplied to the navigation system or audio and visual system when the ignition switch is turned to ON for the first time after the battery has been reconnected, vehicle control history code X087A will be stored. Perform either of the following operations:
      1. Turn the ignition switch from OFF to ON twice.
      2. After turning the ignition switch from OFF to ON, clear the vehicle control history codes.
      3. Enter the following menus: Powertrain / Stop and Start / Utility / Vehicle Control History (RoB) / Clear.
        NOTE:

        By performing this procedure, all stored Vehicle Control History items will be cleared.

        Powertrain > Stop and Start > Utility 

        Tester Display
        Vehicle Control History (RoB)
  5. IF THE ENGINE FAILS TO RESTART FROM IDLING STOP 
    NOTE:

    If the engine fails to restart when stopped by stop and start control, the brake actuator may be activated.

    Brake actuator activation conditions:

    • When the engine fails to restart when stopped by stop and start control.
    • When the vehicle speed is 3 km/h (2 mph) or more and the brake pedal is depressed*.

      *: When the engine is not running.

    HINT: 

    • When the engine fails to restart when stopped by stop and start control and the brake booster vacuum is insufficient, the brake actuator is activated to ensure the braking force.
    • When the brake actuator is activated, sound and vibration may be generated. This is not due to malfunction of the stop and start system or the vehicle.
  6. PRECAUTIONS AFTER CHARGING BATTERY 

    HINT: 

    If the battery is replaced or charged with the cables connected after stop and start control has been prohibited due to a low battery charge, perform the integrated current value initialization using the GTS.

    Refer to REGISTRATION [11/2023 - ] 

    If the Data List item "Integrated Current" indicates 0 A-sec or more, initialization is not necessary.

  7. PRECAUTIONS FOR FOUR-WHEEL TOWING 
    NOTE:
    • When towing the vehicle, its four wheels must be lifted.

      If the vehicle is to be towed with all four wheels on the ground, turn the ignition switch off and then to ON without starting the engine. Only tow the vehicle at speeds below 30 km/h (19 mph) for distances of less than 80 km in a forward direction.

    • If the towing speed or distance exceeds the above limits, or the vehicle is towed backward, the transmission and stop and start system components may be damaged.
  8. PRECAUTIONS WHEN REPLACING ECM 
    NOTE:
    • When the ECM is replaced on a vehicle with a non-specified battery, it is necessary to perform battery type switching.

      Refer to REGISTRATION [11/2023 - ] 

    • Before replacing the ECM, refer to Service Bulletin (for Immobiliser System).
    • Perform Registration (VIN registration or frame number registration) after replacing the ECM.

      Refer to REGISTRATION [10/2022 - ]

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