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Home >> Lexus >> 2017 >> CT 200h Base >> Repair and Diagnosis >> Body & Frame >> Door Locks >> Smart Access System (Keyless Start) (Diagnostics) (Introduction) >> SMART ACCESS SYSTEM WITH PUSH-BUTTON START (for Start Function) >> System Description [08/2014 - ] >> System Description [08/2014 - ]
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System Description [08/2014 - ]

  1. PRECAUTION FOR REGISTRATION 
    1. If replacing any of the following parts, refer to the registration procedures (See article. Refer to REGISTRATION [08/2014 - ] ).
      1. ID code box
      2. Certification ECU (smart key ECU assembly)
      3. Transmission control ECU assembly
      4. Electrical key transmitter (key)
  2. SYSTEM FUNCTION 
    Function Outline
    Ignition function When the key is brought into the vehicle and verified, this function changes the power source or starts the hybrid control system when the power switch and brake pedal are operated.
    Auxiliary battery saving function for vehicle When the vehicle is not used for a long time, this function extends the interval between each periodic transmission of the request signal, or stops transmission of the request signal to save auxiliary battery power.
    • When 5 days elapse without a response from the key, periodic transmission stops.
    • When 14 days elapse without a response from the key, the lock/unlock sensors of all door outside handle assemblies except the driver door are disabled.

    When the key is in the detection area outside the vehicle for 10 minutes or more, this function stops the periodic transmission of the request signal (formation of the detection area) to save auxiliary battery power.
    Battery saving function for key If a switch on the key is depressed and held, this function stops transmission of the signal after approximately 20 seconds to save key battery power.
    Key cancel function Cancels the smart access system with push-button start when certain operations are performed.
    Immobiliser function Allows the hybrid control system to be started only using registered keys to prevent an unauthorized hybrid control system start.
    Automatic power off function
    • With park (P) selected and the power switch on (ACC) (the hybrid control system is not started and the vehicle is not moving), the power automatically turns off when the vehicle is left as is for 20 minutes or more.
    • With park (P) selected and the power switch on (IG) (the hybrid control system is not started and the vehicle is not moving), the power automatically turns off when the vehicle is left as is for 60 minutes or more.
  3. DETECTION AREA 
    NOTE:
    • Depending on the vehicle body shape, the key may not operate in certain locations.
    • Even if the key is in the vehicle exterior key detection area, the key may not be properly detected if the key is near a window, a door handle or the center of the rear bumper.
    • Even if the key is in the vehicle interior key detection area, the key may not be properly detected if the key is on the instrument panel, in the glove box or on the floor.
    • Depending on the way the key is held, the key may not operate properly.
    • The key detection area may reduce in size or the key may not be properly detected under the conditions below:
      • The key battery is depleted.
      • There are TV towers, electric power plants, broadcasting stations, gas stations or other facilities that produce strong electric waves nearby.
      • Wireless products such as cell phones, etc. are carried with the key.
      • The key is covered by or in contact with a metal object.
      • Electric wave-type keyless entry systems are being operated nearby.
      • The key is placed near high-voltage equipment or equipment that emits electrical noise.
    1. The request signal sent from the certification ECU (smart key ECU assembly) is transmitted from each electrical key antenna (outside) to form the smart key detection area. The detection area formed by each electrical key antenna (outside) has a detection range of 0.7 to 1 m (2.30 to 3.28 ft.) from the door handles and rear bumper (electrical key antenna [outside luggage]).
    2. When the vehicle is parked (the power is off and the doors are locked*), the detection area of each electrical key antenna (outside) is formed by emitting a periodic request signal every 0.25 seconds in order to detect the key. Also, when the doors are locked and a lock sensor is touched, a request signal is emitted, the detection area outside the vehicle is formed and the key is detected.

      HINT: 

      *: The smart access system with push-button start controls each door individually. After a door is locked with the door lock sensor or wireless remote control function, a detection area is formed at the locked door even if all the doors are not locked.

    3. The detection area of the electrical key antenna (outside luggage) is formed when the back door opener switch is pressed.
    4. The detection area inside the vehicle is formed and the key is detected when any of the following conditions are met: 1) The driver door is opened and closed, 2) the brake pedal is depressed, 3) the power switch is operated, 4) the conditions required for various warnings are met, or 5) a smart door lock operation is performed.
    5. The detection area inside the vehicle when starting the hybrid control system can be customized through the customize function.