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System Description

WARNING: This page is about a different car, the 2011 Toyota Avalon. However, it is still accessible from the selected car via links, so may be relevant.
  1. SMART KEY SYSTEM DESCRIPTION 
    1. In addition to conventional mechanical key and wireless door lock remote control functions, the smart key system enables door to lock / unlock, steering lock to release, engine to start and luggage compartment to open without operating the key. The only requirement is that the key be in the driver's possession.
      • This system is controlled by the certification ECU. When the certification ECU detects the presence of the smart key system in one of the action area, it identifies and checks the ID code, and outputs operation signals to the related ECU in accordance with their functions.
      • The detection areas are formed by 8 oscillators (4 door oscillators, 2 luggage compartment oscillators, and 2 cabin oscillators).
  2. ACTION AREA 
    Fig 1: Identifying Smart Key System Action Area
    GTY197697Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Precautions for the entire system:
      • Be sure to carry the key during inspection of the smart key system.
      • The key detection area may become small, or the key may not be detected correctly, in the following conditions (As weak radio waves are used to detect the key).
        1. The battery is dead.
        2. Any facilities that generate strong radio waves, such as a TV tower, power plant or broadcast station, are located near the inspection site.
        3. Any wireless applications such as a cellular phone are carried with the key.
        4. The key is in contact or covered with metal.
        5. A radio wave keyless entry system is operated near the inspection site.
        6. The key is located near the device that generates high voltage or noise.
      • The key may be difficult to operate for some reason relating to the vehicle body shape.
      • The key may not be detected correctly if it is around the vehicle's windows, the door handle or center of the bumper even when it is in the detection area outside the vehicle.
      • The key may not be detected correctly if it is on the instrument panel, rear tray or floor, or in the glove box even when it is in the detection area inside the vehicle.
      • The engine cannot be started even when the key is in the detection area inside the luggage compartment.
      • The key may not operate if the key is not held properly.
      • The key emits a weak radio wave. If using a pacemaker, be sure to read the manual of the pacemaker before using the key because this radio wave may affect it.
      • The smart key system does not operate in the following conditions:
        1. The smart key system is cancelled (For detail. Refer to CUSTOMIZE PARAMETERS ).
        2. The key battery is completely dead (The indicator does not blink by pushing any of the buttons on the key) (For details. Refer to INSPECTION ).
  3. FUNCTION OF MAIN COMPONENTS 
    Component Function
    Key The key consists of a mechanical key, the transmitter for the wireless door lock remote control and the transceiver for the smart key system, and a transponder chip for the engine immobilizer control.
    Certification ECU Controls the smart key system in accordance with the signals from each oscillator, various switches, ECUs and key.
    • Judges and certifies the ID code from the tuner.
    • Transmits the engine immobilizer unset signal to the ID code box.
    • Transmits the steering unlock signals to the steering lock ECU.
    Power Source Control ECU Controls the push button start function in accordance with the signals from the various switches, ECUs and combination meter.
    • Transmits the key verification request signal to the certification ECU in accordance with the engine switch signal, and turns the relays ON and OFF.
    ID Code Box Receives the steering unlock or engine immobilizer unset signals from the certification ECU, certifies them, and transmits each unset signal to the steering lock ECU or ECM.
    Body ECU
    • Receives the request signal from the certification ECU and actuates the door lock motor to unlock or lock the door.
    • Transmits each door condition to the certification ECU.
    Outside Handle Antenna Transmits the request signals.
    Touch Sensor Detects when a person touches an outside handle inside.
    Lock Switch Transmits door lock request signals to certification ECU.
    Door Oscillator
    • Front RH and LH
    • Rear RH and LH
    		 Receives the request signal from the certification ECU, and forms the actuation area around each door.
    Cabin Oscillator
    • Front and Rear
    		 Receives the request signal from the certification ECU, and forms the actuation area in the vehicle interior.
    Luggage compartment Oscillator
    • Inner
    		 Receives the request signal from the certification ECU, and forms the actuation area in the luggage compartment.
    Luggage compartment Oscillator
    • Outer
    		 Receives the request signal from the certification ECU, and forms the actuation area around the luggage compartment lid.
    Tuner
    • Receives the ID code from the key in the actuation area and transmits it to certification ECU.
    • Receives the ID code from the key in the luggage compartment and transmits it to certification ECU.
    Outside Rear View Mirror Foot Light When the key enters the exterior actuation area, the foot light is illuminated in accordance with the request signal of the certification ECU.
    Luggage compartment Open Switch Transmits a luggage compartment lid open request signal to Certification ECU.
    Stop Light Switch Outputs the state of the brake pedal to the power source control ECU.
    Wireless Door Lock Buzzer When the certification ECU detects human errors such as the following, it warns the driver by sounding the wireless door lock buzzer, illuminating the key warning light and sounding the buzzer in accordance with the request signal from the ECU.
    Example: 
    • The key is taken outside the vehicle.
    • The driver gets out while the engine is still running.
    • The driver gets out while the shift is in a position other than "P".
    Combination Meter Key Warning Light
    Buzzer
    Accessory Meter
  4. CONSTRUCTION AND OPERATION 
    1. Key

      The key consists of a mechanical key, a transmitter function for the wireless door lock remote control and a transceiver for the smart key system, and a transponder chip for the engine immobilizer control.

      • The transceiver function for the smart key system receives the signals from the oscillators and returns the ID code to the tuner.
      • The transmitter function for the wireless door lock remote control has a LOCK button, UNLOCK button, LUGGAGE OPEN button, PANIC button.
      • The transponder chip for the engine immobilizer control returns to the engine switch the radio wave response it received from the engine switch.
      • This mechanical key works for the driver door, luggage compartment storage extension and glove box, but cannot start the engine.

      A total of four keys can be registered. For details. Refer to REGISTRATION .

      Fig 2: Identifying LOCK Button, UNLOCK Button, LUGGAGE OPEN Button And PANIC Button
      GTY197693Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Oscillator (Each Door, Front and Rear Cabins, Luggage compartment Inner, luggage compartment Outer)

      Each oscillator transmits the request signal received from the certification ECU, and forms a key actuation area to detect the presence of a key.

      The actuation area formed by each door oscillator and luggage compartment outer oscillator is approximately 0.7 to 1.0 m (2.3 to 3.3 ft.) from the outside handle of each door, or the center of the rear bumper.

      • The actuation area of each door oscillator is formed by transmitting a request signal every 0.25 seconds while the engine switch is off and each door is locked. In this way it detects the proximity of a key. During entry lock, the actuation area is formed with the lock switch on.
      • The actuation area of the luggage compartment outer oscillator is formed when the luggage compartment open switch is on. It is formed twice until the key can be verified.
      • The actuation area of the front and rear cabin oscillator is formed when the driver door is opened or closed, during start ignition, when a warning is activated, or when the lock switch is on.
      • The actuation area of the luggage compartment inner oscillator forms when the luggage compartment lid is closed or the luggage compartment open switch is pressed, and is formed twice until the key can be verified.
  5. ENTRY FUNCTION OPERATION 
    1. The smart key system has the following functions.
      Function Outline
      Mechanical Key The operation is same as mechanical key.
      Wireless Door Remote Control This function is a convenient system for locking and unlocking all the doors or luggage compartment at a distance. The operation is same as wireless door lock remote control system. However, the receiver in the certification ECU uses a tuner to perform control.
      Entry Illumination When a key enters any actuation area of the door oscillator, the foot light, the front interior light, and engine switch illumination illuminate.
      Entry Unlock When a key is located in any actuation area of the door oscillator, the door will unlock with the touch of an outside door handle.
      Entry Unlock Mode Switching. Refer to CUSTOMIZE PARAMETERS  Switches the doors that can be unlocked with the entry unlock function in two modes.
      • Driver Door Mode
      • All Door Mode
      Entry Lock When a key is located in any actuation area of the door oscillator and the power source is OFF, the door will be locked by merely pressing the lock switch on the outside door handle.
      Entry Luggage compartment Open When a key is in an actuation area of the luggage compartment outer oscillator, the luggage compartment opens by merely pressing the luggage compartment open switch.
      Memory Call This function operates the memory system in accordance with key ID.
      Prevention of Key Confinement (*1)
      • Prevents the confinement of the key if the door is locked from the outside door handle while the key is still inside the vehicle.
      • If the luggage compartment lid is closed while the key is still in the luggage compartment, the warning buzzer sounds, If the luggage compartment open switch is operated in two seconds during this period, the luggage compartment lid can be opened.
      Warning When any of the situations below occur, the smart key system causes certification ECU to sound the buzzer in the combination meter and wireless door lock buzzer, and illuminate the key warning light in order to the alert the driver.
      • An exit warning if the shift lever is in a position other than "P" and the power source is a mode other than "OFF".
      • An exit warning if the shift lever is in "P" and the power source is a mode other than "OFF".
      • A warning if the occupant leaves with the key.
      • A warning if the engine switch is operated while the key is outside the actuation area.
      • A warning if the entry lock is operated while the key is inside the vehicle.
      • A warning if the key battery is weak.
      Battery Saving If the key is constantly located within any actuation area of the door oscillator, the system maintains periodic communication with key. Therefore, if the vehicle remains parked in that state for a long time, the key battery and the vehicle battery could be drained.
      Key Cancel. Refer to CUSTOMIZE PARAMETERS  The following key functions can be cancelled by following certain operations.
      • Entry Unlock / Lock
      • Entry Unlock Mode Switching
      • Entry Luggage compartment Open
      • Prevention of Key Confinement
      • Warning
      Push Button Start When a key is located in any actuation area of the cabin oscillator, the power source mode can be switched by operating the engine switch.

      *1: "Prevention of key confinement" function activates only when all the doors are locked.

  6. Wireless door lock and unlock and luggage compartment open function 

    Push the LOCK / UNLOCK / PANIC / LUGGAGE COMPARTMENT button on the key to operate each function.

  7. Entry unlock function 
    1. The action area is formed by regular communication between the door oscillator and tuner when the door is locked in order to detect access of the person carrying the key.
    2. When the person carrying the key enters the action area around the vehicle, the matching of the ID codes for the door oscillator and key will automatically be performed. After the matching is completed, the door will enter unlock standby mode.
    3. In unlock standby mode, the antenna built into the outside handle starts. If the outside handle is held (the back side of the handle is touched), the door unlock operation will be performed. (If the ID codes do not match, the door unlock operation for that door can not be done by holding the outside handle.) At this time, the hazard warning light blinks twice and the wireless door lock buzzer sounds twice.
    4. If any of the doors is not opened after door unlock operation, all doors will automatically lock after 30 seconds.
  8. Entry lock function 
    1. After leaving the vehicle carrying the key, push the lock switch on the outside handle when all the doors are closed.
    2. The certification ECU determines whether the key is located inside or outside of the cabin based on the information of the door oscillator and cabin oscillator. The matching of the ID codes is performed.
    3. When the matching result shows that the ID codes of the key and cabin oscillator do not match and those of the key and door oscillator match, the door lock function will operate. As this time, the hazard warning light blinks once and the wireless door lock buzzer sounds once.
    4. If the key is located inside of the cabin, the door lock function will not operate and the alarm buzzer (peep sound) will sound for 2 seconds.
  9. Push button start function 
    1. When all the power sources of the vehicle are off, get in the vehicle carrying the key. Push the engine switch with the brake pedal released to perform matching of the ID codes inside of the cabin. If the codes match, the engine switch will light up in amber. The engine switch will change between ACC, IG, and OFF every time the engine switch is pushed. If the engine switch is pushed when the engine switch is ON (IG) with the shift lever in a position other than P and N, the engine switch will change to ON (ACC), not to OFF.
    2. When all the power source of the vehicle are off, get in the vehicle carrying the key. When the brake pedal is depressed with the shift lever in the P or N position, the matching of the ID codes will be performed inside the cabin. If the ID codes match, the indicator of the engine switch will light up in green. While the indicator lights up in green, push the engine switch to start the engine.
  10. Push button start function (Key battery is dead) 
    1. Get in the vehicle carrying the key (Use the mechanical key built into the key to unlock the door). Depress the brake pedal and hold the ornament face of the key to the engine switch so that the distance between them is 10 mm or less.
      Fig 3: Identifying Communication Distance Between Engine Switch And Key
      GTY197696Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Release the brake pedal and push the engine switch within 5 seconds after a pip buzzer sounds. The engine switch will light up in amber. The engine switch will change between ACC, IG, and OFF every time the engine switch is pushed If the engine switch is pushed when the engine switch is ON (IG) with the shift lever in a position other than P and N, the engine switch will change to ON (ACC), not OFF.

    2. Get in the vehicle carrying the key (Use the mechanical key built into the key to unlock the door). Depress the brake pedal with the shift lever in the P or N position and hold the ornament face of the key to the engine switch so that the distance between them is 10 mm or less.

      The indicator of the engine switch lights up in green after a pip buzzer sounds. Push the engine switch with the brake pedal depressed within 5 seconds of the buzzer sound.

  11. Engine stop - Steering lock function / Engine immobilizer set function 

    If the engine switch is pushed after the vehicle stops, the engine and all the power sources will turn off. If the engine switch is pushed when the vehicle stops with the shift lever in a position other than P and N, the engine switch will change to ON (ACC), not to OFF.

    If the driver's door is opened with the shift lever in the P position, steering lock will operate.

  12. Entry luggage compartment open function 

    Stand in front of the luggage compartment with the key and push the luggage compartment open switch to start the matching of the ID codes for the luggage compartment oscillator (outer). If the ID codes match, luggage compartment open operation will be performed.

  13. Prevention of key confinement function 
    1. If you attempt to lock the door through keyless operation (move the lock knob to the lock position and then close the door) with the key in the cabin, the system determines that the key is located in the cabin and unlocks the door.
    2. If the luggage compartment is closed with the key in it, the alarm will sound and the luggage compartment can be opened only when all the doors are locked in order to prevent key confinement in the vehicle.

      HINT: 

      "Prevention of key confinement" function activates only when all the doors are locked.

  14. Entry illumination function 
    1. When a person carrying the key enters the action area, the door will enter unlock standby mode and the front dome light and door mirror foot light will light up.

      HINT: 

      The smart illumination function operates when the key enters the detection area from out of the detection area outside of the cabin (for 3 seconds or more). If the key remains in the detection area, the illumination function does not operate.

  15. Memory call function 

    When the driver's door is opened or the engine switch is turned ON (ACC, IG), the seat position, etc. will automatically be restored to the state that has been set for the key code.

    For the procedures of key registration. Refer to REGISTRATION  and cancellation. Refer to CUSTOMIZE PARAMETERS .

  16. Warning Function 
    1. General

      When any of the situation below occurs, the smart key system causes certification ECU to sound the buzzer in the combination meter and the wireless door lock buzzer, and illuminate the key warning light in order to alert the driver.

      1. An exit warning if the shift lever is in a position other than "P" and the power source is a mode other than "OFF".
      2. An exit warning if the shift lever is in "P" and the power source is a mode other than "OFF".
      3. A warning if the occupant leaves with the key.
      4. A warning if the engine switch is operated while the key is outside the actuation area.
      5. A warning if the entry lock is operated while the key is inside the vehicle.
      6. A warning if the key battery is weak.
    2. Situation: A

      There are two patterns for situation A.

      Pattern 1. In situation a), the door is opened and the user tries to leave the vehicle.

      Pattern 2. Then the user holds the key and tries to move away from the vehicle.

      In these situations the following control is performed.

      PATTERN 1.

      Possible Effects without Warning Sudden vehicle start, Vehicle roll-away
      Warning Condition The certification ECU gives a warning when all the following conditions are satisfied.
      • Shift lever is except "P".
      • Power source mode is except "OFF".
      • Driver door is opened.
      • Vehicle speed is 0.
      Combination Meter Buzzer Warning: Continuous sound
      The warning is stopped when one of the following conditions are met.
      • Power source mode is "OFF".
      • Shift lever is "P".
      • Vehicle speed is above 0.
      Key Warning Light -
      Wireless Door Lock Buzzer -
      PATTERN 2.

      Possible Effects without Warning Sudden vehicle start, Vehicle theft, Vehicle roll-away
      Warning Condition The certification ECU gives a warning when all the following conditions are satisfied.
      • Shift lever is except "P".
      • Power source mode is except "OFF".
      • Driver door changed from open to close.
      • Vehicle speed is 0.
      • Key is not in the vehicle.
      Combination Meter Buzzer Warning: Continuous sound
      The warning is stopped when one of the following conditions is met.
      • Power source mode is "OFF"
      • Shift lever is "P".
      • Vehicle speed is above 0.
      Key Warning Light Warning: Turn ON
      The warning is stopped when one of the following conditions is met.
      • Power source mode is "OFF".
      • Key is in the vehicle.
      Wireless Door Lock Buzzer Warning: Continuous sound
      The warning is stopped when one of the following conditions is met.
      • Power source mode is "OFF".
      • Shift lever is "P".
      • key is in the vehicle.
      • Vehicle speed is above 0.
    3. Situation: B

      There are three patterns for situation B.

      Pattern 1. In situation b), the door is opened and the user tries to leave the vehicle.

      Pattern 2. Then the user holds the key and tries to move away from the vehicle.

      Pattern 3. Then the user tires to use the entry lock and presses the lock switch.

      In these situations the following control is performed.

      PATTERN 1.

      Possible Effects without Warning Vehicle theft
      Warning Condition The certification ECU gives a warning when all the following conditions are satisfied.
      • Shift lever is "P".
      • Power source mode is except "OFF".
      • Driver door is opened.
      Combination Meter Buzzer Warning: Discontinuous sound
      The warning is stopped when one of the following conditions is met.
      • Power source mode is "OFF".
      • Shift lever is except "P".
      • Driver door is closed.
      Key Warning Light -
      Wireless Door Lock Buzzer -
      PATTERN 2.

      Possible Effects without Warning Vehicle theft, Engine cannot be restarted
      Warning Condition The certification ECU gives a warning when all the following conditions are satisfied.
      • Shift lever is "P".
      • Power source mode is not "OFF".
      • Driver door changed from open to closed.
      • key is not in the vehicle.
      Combination Meter Buzzer Warning: Sound once
      Key Warning Light Warning: Turn ON
      The warning is stopped when one of the following conditions is met.
      • Power source mode is "OFF".
      • Key is in the vehicle.
      Wireless Door Lock Buzzer Warning: Sound 3 times
      The warning is stopped when one of the following conditions is met.
      • Power source mode is "OFF".
      • Vehicle speed is above 0.
      PATTERN 3.

      Possible Effects without Warning Vehicle theft
      Warning Condition The certification ECU gives a warning when all the following conditions are satisfied.
      • Shift lever is "P".
      • Power source mode is not "OFF".
      • All doors are closed.
      • Lock switch is "ON".
      • Key is outside the vehicle.
      Combination Meter Buzzer -
      Key Warning Light -
      Wireless Door Lock Buzzer Warning: Sounds for 2 seconds
    4. Situation: C

      In this situation the following control is performed.

      Possible Effects without Warning Engine cannot be restarted
      Warning Condition The certification ECU gives a warning when all the following conditions are satisfied.
      • Power source mode is not "OFF".
      • Any door but the driver's changed from open to close.
      • Vehicle speed is 0.
      • Key is not in the vehicle.
      Combination Meter Buzzer Warning: Sound once
      Key Warning Light Warning: Turn ON
      The warning is stopped when one of the following conditions is met.
      • Power source mode is "OFF".
      • Vehicle speed is above 0.
      Wireless Door Lock Buzzer Warning: Sound 3 times
      The warning is stopped when one of the following conditions is met.
      • Power source mode is "OFF".
      • Vehicle speed is above 0.
    5. Situation: D

      In this situation the following control is performed.

      Possible Effects without Warning Confuses the user
      Warning Condition The certification ECU gives a warning when all the following conditions are satisfied.
      • Engine switch is pushed.
      • Key is not in the vehicle.
      Combination Meter Buzzer Warning: Sound once
      Key Warning Light Warning: Turns ON for 5 seconds
      Wireless Door Lock Buzzer -
    6. Situation: E

      In this situation the following control is performed.

      Possible Effects without Warning Vehicle theft
      Warning Condition The certification ECU gives a warning when all the following conditions are satisfied.
      • Power source mode is "OFF".
      • All doors are closed.
      • Lock switch is "ON".
      • Key is in the vehicle.
      Combination Meter Buzzer -
      Key Warning Light -
      Wireless Door Lock Buzzer Warning: Sounds for 2 seconds
    7. Situation: F

      In this situation the following control is performed.

      Possible Effects without Warning Smart key system does not function
      Warning Condition The certification ECU gives a warning when all the following conditions are satisfied.
      • Power source mode switches to OFF after being left in IG-ON for over 20 minutes.
      • Key battery voltage is low.
      Combination Meter Buzzer Warning: Sound once
      Key Warning Light -
      Wireless Door Lock Buzzer -
  17. Battery Saving 
    1. Vehicle Battery Saving Function

      In the smart key system, signals are emitted outside of the vehicle at a prescribed interval (300 ms) when the doors are locked. Therefore, the vehicle battery could be drained if the vehicle remains parked for a long time. For this reason, the controls listed below are effected.

      Condition Control
      No response from key for more than 5 days Signal transmission interval is extended from 250 ms to 750 ms.
      No response from key for more than 14 days Automatically deactivates the smart key system.

      Reinstatement Conditions 

      • A wireless door lock remote control signal (lock, unlock, or luggage compartment lid open) is input and the ID matches.
      • A user carries the key and pushes a lock switch signal for the outside door handle.
      • A door is locked or unlocked by the mechanical key.
    2. Key Battery and Vehicle Battery Saving Function

      In the smart key system, if the key is constantly located within the vehicle exterior actuation area of the doors, the system maintains periodic communication with the key. Therefore, if the vehicle remains parked in that state for a long time, the key battery and the vehicle battery could be drained. For this reason, if this state continues longer than 10 minutes, the smart key system automatically becomes deactivated.

      Reinstatement Conditions 

      • A wireless door lock remote control signal (lock, unlock, or luggage compartment lid open) is input and the ID matches.
      • A user carries the key and pushes a lock switch signal for the outside handle.
      • A door is locked or unlocked by the mechanical key.
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