ROAD SIGN ASSIST SYSTEM


  1. FUNCTION OF MAIN COMPONENTS


    1. The main components in the RSA have the following functions.

      Components Function
      Forward Recognition Camera

      • Captures road signs.

      • Performs RSA system control based on information of road signs captured.

      • Sends an operation signal to the camera heater.
      Camera Heater (Forward Recognition Hood with Heater Sub-assembly) The camera heater is heated according to signals from the forward recognition camera.
      Millimeter Wave Radar Sensor Assembly Detects object information and sends a signal to the forward recognition camera.
      Hybrid Vehicle Control ECU Assembly Sends the shift position signal to the forward recognition camera.
      Skid Control ECU Assembly Sends a vehicle speed signal to the forward recognition camera.
      Steering Pad Switch Assembly Meter Control Switch Sends a multi-information operating signal to the combination meter assembly.
      Combination Meter Assembly Sends a turn signal command to the forward recognition camera.
      Combination Meter Assembly Multi-information Display

      • Displays road signs recognized by the forward recognition camera.

      • The RSA system can be turned on and off through the settings tab.
      Master Warning Light Illuminates when there is a malfunction in the RSA system.
      Meter Buzzer Sounds when the speed limit is exceeded or no overtaking notifications are issued.*1
      Yawrate Sensor Detects the yaw rate and sends it to the forward recognition camera.
      Air Conditioning Amplifier Assembly Sends the outside air temperature to the forward recognition camera.
      Steering Sensor

      • Sends the turning angle of the steering wheel to the forward recognition camera.

      • Sends a turn signal command to the combination meter assembly.
      Turn Signal Switch Sends a turn signal command to the steering sensor.
      Headup Display (Meter Mirror Sub-assembly)*2 Displays road signs recognized by the forward recognition camera.
      Main Body ECU (Multiplex Network Body ECU) Sends country specification information signals to the forward recognition camera.
      Radio Receiver Assembly*3 Sends map information from the navigation ECU to the forward recognition camera.
      Navigation ECU*3

      • Sends map information to the radio receiver assembly.

      • Performs coordinated control with the forward recognition camera in regards to speed limit information.
      Central Gateway ECU (Network Gateway ECU) Relays the signal between the CAN communication buses.
      DLC3 The Global TechStream (GTS) can be connected to read the Diagnostic Trouble Codes (DTCs) of malfunctions.

      *1: The threshold can be adjusted to 1 of 3 levels through the customization function.

      *2: Models with headup display

      *3: Models with navigation system

  2. FUNCTION


    1. The RSA system recognizes the following traffic signals using the forward recognition camera.

      Category Sign Type Example of Recognizable Sign
      Speed Limit Round maximum speed limit/End of speed limit A004CGE
      No Overtaking No overtaking/End of no overtaking A004C4R
      Supplemental Signs Road condition signs Ramp Way A004CRA
      Rain A004BZ3
      Wet A004CFT
      Ice A004CAA
      End of Prohibition A004C12
      No Entry* A004C73

      *: Models with navigation system

    2. The RSA system recognizes the following traffic signals using the forward recognition camera.

      Category Display Example Details
      Speed Limit Related A004C99

      • Informs the driver of the maximum speed limit of the currently driven road.

      • The displayed sign reflects the speed limit on the recognized sign.
      No Overtaking Related A004CSP Informs the driver when they are in a no overtaking zone on the currently driven road.
      No Entry* A004C73 Informs the driver that there are vehicle entry restricted sections on the currently driven road.
      All Canceled (All restrictions canceled. Return to default road regulations.) A004C12 Informs the driver when all applicable prohibitions, such as speed limit and no overtaking, have ended.
      Speed Limit with Supplemental Sign Related Ramp Way A004CFM Informs the driver of the ramp way direction. However, this item is not displayed when making a lane change without operating the turn signal light.
      Rain A004C8W Informs the driver of the maximum speed limit on the currently driven road when it is raining or the road surface is wet.
      Ice A004CGH Informs the driver of the maximum speed limit on the currently driven road when there is accumulated snow or ice.
      Blank A004CTV The display is blank when the system is unable to recognize a supplemental sign.

      *: Models with navigation system

      Tech Tips

      A non-official (sign not meeting Vienna Convention) or a recently introduced traffic sign may not be recognized.

    3. Notification functions are used in the RSA system which invert the colors of displayed signs, flash signs, etc. to notify the driver.


      1. Speed Limit Exceeded Notification


        • While a speed limit sign is displayed, if the actual vehicle speed exceeds the speed limit plus a designated threshold*, the colors of the displayed sign are inverted. For example, if the threshold is set to 5 km/h and the speed limit sign is 60 km/h, the colors of the displayed sign are inverted when the actual vehicle speed exceeds 65 km/h. Furthermore, the system also inverts a speed limit sign with supplemental sign in the same way. However, the system does not invert the colors of the supplemental sign.

        • The meter buzzer may be set to sound during notifications through the customization function. However, if a speed limit recognized from a speed limit with supplemental sign is exceeded, the meter buzzer does not sound.

        • This notification is judged according to the speed units estimated by the forward recognition camera. When moving to a region with different speed units, notifications may be incorrectly issued until learning is complete. (The user can change speed units of the meter for the given region. Therefore, displays and notifications can be correctly issued directly after moving to a region with different speed units.)

          Tech Tips

          *: The threshold can be adjusted to 1 of 3 levels through the customization function.

        Notification Method Display Example
        Inverted Display A004C4L

      2. No Overtaking Notification


        • While a no overtaking sign is displayed, if the system detects that the vehicle is attempting to overtake another vehicle, the system flashes the displayed sign.

        • The meter buzzer may be set to sound during notifications through the customization function.

        Notification Method Display Example
        Flashing Display A004CCM

      3. No-entry Notification*


        • While a no entry sign is displayed, if the system detects that the driver is driving on a road where entry is prohibited, based on map information, the system flashes the displayed sign.

        • The meter buzzer may be set to sound during notifications through the customization function.

        Notification Method Display Example
        Flashing Display A004CGJ

        • *: Models with navigation system

    4. The RSA system can be turned on or off through the settings tab of the multi-information display.

    5. A customization function is used for the RSA, which allows settings such as the notification method and level for exceeding the speed limit to be changed. Setting changes are made through the customization tab of the multi-information display. Refer to the Repair Manual for details.

  3. SYSTEM CONTROL


    1. RSA Control Pattern 1


      1. After a road sign is recognized by the forward recognition camera and the vehicle passes by, the sign is displayed on the multi-information display and headup display*.

      2. While a sign is displayed on the multi-information display and headup display*, if a new road sign is not recognized within a specified distance, display of the current sign is turned off.


        • *: Models with headup display

        A004CCBE01
        *1 Road Sign Recognized
        *2 Specified Distance Driven
        *3 Sign display off
        *4 Sign display on

    2. RSA Control Pattern 2


      1. When the power switch is turned off while a sign is displayed on the multi-information display and headup display*, the same sign is displayed when the power switch is turned on (IG) again.


        • *: Models with headup display

        A004CIUE01
        *1 Power Switch is Turned Off
        *2 Power Switch is Turned On (IG)
        *3 Sign display on

    3. RSA Control Pattern 3


      1. While a sign is displayed on the multi-information display and headup display*, the sign is turned off when turning left or right onto a new road.


        • *: Models with headup display

        A004CTRE01
        *1 Road Sign Recognized
        *2 Sign display off
        *3 Sign display on

  4. DIAGNOSIS


    1. If a malfunction is detected in the RSA system, the forward recognition camera cancels the RSA system, sounds the meter buzzer, and displays a message on the multi-information display to inform the driver of the malfunction.

    2. At the same time, the malfunction is stored in memory as a Diagnostic Trouble Code (DTC). For details, refer to the Repair Manual.