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Home >> Toyota >> 2010 >> RAV4 Base, 2.5 F, FWD >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 36 (Smart Key System (Keyless Start) (2GR-FE) (Diagnostics - Introduction)) >> Smart Key System >> System Description >> System Description
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System Description

WARNING: This page is about a different variant/trim than selected.
  1. PUSH-BUTTON START DESCRIPTION 
    1. The push-button start uses a push-type engine switch, which the driver can operate by merely carrying the key. This system consists primarily of the main body ECU, engine switch, ID code box, steering lock ECU, key, ACC relay, IG1 relay, IG2 relay and certification ECU. The main body ECU controls the system. This function operates in cooperation with the smart key system. The table below shows the transition of the engine switch state, which depends on whether the brake pedal is depressed or released.
    2. This system has different power source mode patterns depending on the brake pedal condition.
      Brake Pedal Power Source Mode Pattern
      Not depressed, shift lever in P Each time engine switch is pushed
      • off → on (ACC) → on (IG) → off
      Not depressed When engine switch is pushed in engine started condition
      • Engine started → off
      Depressed, shift lever in P or N When engine switch is pushed once
      • off → engine start
      Depressed, shift lever in P or N When engine switch is pushed in on (ACC) condition
      • on (ACC) → engine start
      Depressed, shift lever in P or N When engine switch is pushed in on (IG) condition
      • on (IG) → engine start
      Depressed When engine switch is pushed in engine started condition
      • Engine started → off

      When the battery of the key is low, the push-button start function can be operated by holding the key against the engine switch.

  2. FUNCTION OF COMPONENT 
    Component Function
    Engine Switch
    (Transponder Key Amplifier)
    • Transmits the engine switch signal to the main body ECU.
    • Informs the driver of the power source mode or a system abnormality with the indicator light illumination.
    • Receives the ID code and transmits it to the certification ECU when the battery of the key is low.
    Key
    • Receives signals from the oscillators and transmits the ID code to the door control receiver.
    Indoor Electrical Key Oscillator
    • Receives a request signal from the certification ECU and forms a detection area in the vehicle interior.
    Door Control Receiver
    • Receives the ID code from the key and transmits it to the certification ECU.
    Main Body ECU
    • Changes the power source mode in 4 stages (off, on (ACC), on (IG), start) in accordance with the state of the park/neutral position switch.
    • Controls the push-button start function in accordance with signals received from switches and each ECU.
    Certification ECU
    • Certifies the ID code received from the door control receiver and transmits the certification results to the ID code box and steering lock ECU.
    Park/Neutral Position Switch
    • Outputs the state of the shift lever to the main body ECU.
    Stop Light Switch
    • Outputs the state of the brake pedal to the main body ECU.
    ID Code Box
    • Receives 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.
    ECM
    • Receives the engine start request signal from the main body ECU, turns on the ST CUT relay, and starts the engine.
    • Receives a signal from the ID code box and performs engine ignition and fuel injection.
  3. SYSTEM FUNCTION 

    The electric controls of the push-button start function are described below:

    Control Outline
    Engine Switch Control
    • When the driver operates the engine switch while in possession of the key, the certification ECU starts the indoor electrical key oscillator, which transmits a request signal to the key. Upon receiving this signal, the key transmits the ID code signal to the main body ECU.
    • The ID code box verifies the check results received from the certification ECU via the LIN line and sends them to the main body ECU. Based on these results, the main body ECU authorizes operation of the engine switch.
    Diagnosis
    • When the main body ECU detects a malfunction, the main body ECU diagnoses and memorizes the failed section.
  4. CONSTRUCTION AND OPERATION 
    Fig 1: Identifying Indicator Light
    GTY104304Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Engine switch:

      The engine switch consists of a momentary type switch, color (amber, green) LED, and the transponder key amplifier.

      • The amber LED is for illumination.
      • The amber and green LEDs are for the indicator light. The driver can check the present power source mode and whether the engine can start or not by checking the illumination state of the indicator light.
      • When the main body ECU detects an abnormality in the smart key system, it makes the amber indicator light flash. If the engine stops in this state, it might not be possible to restart it.
    2. Indicator light condition:
      ENGINE SWITCH INDICATOR LIGHT CONDITION

      Power Source Mode/Condition Indicator Light Condition
      Brake Pedal Released Brake Pedal Depressed and Shift Lever in P or N
      Off Off Illuminates (green)
      On (ACC) or on (IG) Illuminates (amber) Illuminates (green)
      Engine running Off Off
      Steering lock locked Flashes (green) for 30 seconds Flashes (green) for 30 seconds
      System malfunction Flashes (amber) for 15 seconds Flashes (amber) for 15 seconds
      Stop light switch malfunction with shift lever in P or N Flashes (green) for 15 seconds Flashes (green) for 15 seconds
    3. Main body ECU:

      The main body ECU consists of the IG1 and IG2 relay actuation circuits and CPU.

  5. WHEN KEY BATTERY IS LOW 
    Fig 2: Identifying Electrical Key
    GTY213990Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. To operate the push-button start function when the key battery is low, touch the TOYOTA mark of the key to the engine switch while depressing the brake pedal with the shift lever in P or N.
    2. The main body ECU transmits a key verification request signal from the stop light switch to the certification ECU.
    3. The certification ECU does not receive an ID code response from the door control receiver, so it actuates the transponder key amplifier built into the engine switch.
    4. The transponder key amplifier outputs an engine immobilizer radio wave to the key.
    5. The key receives the radio wave, and returns a radio wave response to the transponder key amplifier.
    6. The transponder key amplifier combines the key ID codes with the radio wave response and transmits it to the certification ECU.
    7. The certification ECU judges and verifies the ID code, and transmits a key verification OK signal to the main body ECU. The buzzer in the combination meter sounds at the same time.
    8. After the buzzer sounds, with the shift lever in P or N, if the engine switch is pressed within 5 seconds with the brake pedal not depressed and the shift lever in P or N, the power source mode changes to on (ACC) or on (IG), which is the same as under normal operation.
  6. DIAGNOSIS 

    The main body ECU can detect malfunctions in the push-button start function when the power source mode is on (IG).

    When the ECU detects a malfunction, the amber indicator light of the engine switch flashes to warn the driver. At the same time, the ECU stores the 5-digit DTC (Diagnostic Trouble Code) in memory.

    • The indicator light warning continues for 15 seconds even after the power source mode is changed to off.
    • The DTCs can be checked by connecting the intelligent tester to the DLC3.
    • The push-button start function cannot be operated if a malfunction occurs.
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