ROAD SIGN ASSIST SYSTEM


  1. FUNCTION OF MAIN COMPONENTS

    Components Function
    Forward Recognition Camera Monocular Camera Sensor Captures road signs.
    Forward Recognition Camera ECU

    • Performs RSA system control based on road sign information captured by the monocular camera.

    • Transmits an operation signal to the camera heater.*1
    Camera Heater (Forward Recognition Hood with Heater Sub-assembly)*1 The camera heater is heated according to signals from the forward recognition camera.
    Millimeter Wave Radar Sensor Assembly detects object information and sends signal to 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.
    Multi Buzzer Sounds for speed limit exceeded and no overtaking notifications.*2
    Steering Pad Switch Assembly Meter Control Switch Sends multi-information operating signals to the forward recognition camera.
    Power Management Control ECU Sends shift position signals to the forward recognition camera.
    Skid Control ECU Assembly Sends vehicle speed signals from the speed sensor to the forward recognition camera.
    Main Body ECU (Multiplex Network Body ECU) Sends country specification information signals to the forward recognition camera.
    Yawrate Sensor Detects the yaw rate and lateral/longitudinal deceleration of the vehicle and transmits the signal to the forward recognition camera.
    Combination Meter Mirror ECU*3 Shows the road signs in accordance with a signal from the combination meter assembly.
    Speed Sensors Detects the wheel speed of each of the 4 wheels and outputs it to the skid control ECU assembly.
    Air Conditioning Amplifier Assembly Transmits the outside air temperature to the forward recognition camera.
    Multi-media Module Receiver Assembly Sends map information signals to the forward recognition camera.
    Central Gateway ECU Gateway function of CAN communication.

    Tech Tips

    *1: Models with camera heater

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

    *3: Models with headup display

  2. FUNCTION


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

      Category Sign Type Example of Recognizable Traffic Sign
      Speed Limit Round maximum speed limit/End of speed limit B002B39
      No Overtaking No overtaking/End of no overtaking B002B1X
      Supplemental signs Road condition signs Ramp way B002B3C
      Rain B002B22
      Ice B002B1J
      Wet B002AXH
      End of prohibition B002B1L
      No entry B002AYJ

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

      Category Display Example Details
      Speed limit related B002B1N

      • 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 B002B3L Informs the driver when they are in a no overtaking zone on the currently driven road
      All canceled (All restrictions canceled. Return to default road regulations.) B002B1L Informs the driver when all applicable prohibitions, such as speed limit and no overtaking, have ended.
      Speed limit with supplemental sign related Ramp way B002AYY 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 B002B1K Informs the driver of the maximum speed limit on the currently driven road when it is raining or the road surface is wet.
      Ice B002B12 Informs the driver of the maximum speed limit on the currently driven road when there is accumulated snow or ice.
      Blank B002B00 The display is blank when the system is unable to recognize a supplemental sign.

    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 multi 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 multi 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. By doing this, 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 B002AYB

      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 multi buzzer may be set to sound during notifications through the customization function.

          Notification Method Display Example
          Blink B002AY4

      3. No Entry Notification


        • While no entry sign is recognized by the system, if the system detects the vehicle approaching to the no entry road, then system warns to the driver.

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

          Notification Method Display Example
          Blink B002AYZ

  3. SYSTEM CONTROL


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

    2. A customization function is used for the RSA system, 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. 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.

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

        B002AX5E01
        *1 Road Sign Recognized
        *2 Specified Distance Driven
        *3 Sign Display Off
        *4 Sign Display On

    4. RSA Control Pattern 2


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

        B002B3ZE01
        *1 Engine Switch is Turned Off
        *2 Engine Switch is Turned to On (IG)
        *3 Sign Display On

    5. RSA Control Pattern 3


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

        B002B2VE01
        *1 Road Sign Recognized
        *2 Sign Display Off
        *3 Sign Display On

  4. FUNCTION


    1. Forward Recognition Camera


      1. The forward recognition camera is composed of a monocular camera and forward recognition camera ECU.

      2. The RSA system is controlled by the forward recognition camera.

        B002AX1E01
        Text in Illustration
        *1 Forward Recognition Camera - -
        *a Monocular Camera - -

      3. Road signs captured by the monocular camera are output to the forward recognition camera ECU.

      4. The forward recognition camera ECU judges road signs recognized by the monocular camera and displays information based on these judgments on the multi-information display

        B002AXTE01

      5. When one of the following operations is conducted, the forward recognition camera angle must be adjusted. For details, refer to the Repair Manual.


        • - The forward recognition camera is removed and reinstalled or replaced.

        • - Parts relating to the tires or suspension are replaced or adjusted.

        • - Strong force is applied onto the forward recognition camera.

    2. Camera Heater (Forward Recognition Hood with Heater Sub-assembly) (Models with Camera Heater)


      1. The camera heater, which is installed between the forward recognition camera and windshield glass, is heated according to signals from the forward recognition camera in order to prevent the windshield glass on the front of the forward recognition camera from fogging, and also to remove fog buildup. For details, see the PRE-CRASH SAFETY SYSTEM section.

  5. OPERATION


    1. Combination Meter


      1. The combination meter assembly displays recognized signs on the multi-information display based on information of road signs recognized by the forward recognition camera.

      2. The RSA system display mode can be selected by switching the display mode of the multi-information display through operation of the meter control switch of the steering pad switch assembly.

      3. When the driving assist system information tab is selected for display on the multi-information display, road signs recognized by the forward recognition camera are shown on the upper portion of the multi-information display.

      4. A maximum of 3 signs can be displayed simultaneously. When 3 signs are displayed, the signs are displayed in the following order from left to right: speed limit related, speed limit with supplemental sign related and no overtaking or no entry related*.

        Tech Tips

        *: No entry signs have higher priority than speed limit signs.

        B002AYLE01
        Text in Illustration
        *a Speed Limit Related *b Speed Limit with Supplemental Sign Related
        *c No Overtaking or No Entry Related *d The illustration shown is an example only. The illustration may differ from the actual vehicle screen.

      5. When an information tab other than the driving assist system information tab is selected for display on the multi-information display, road signs recognized by the forward recognition camera are displayed as pop-ups on the lower right portion of the multi-information display. Furthermore, the pop-up display is for speed limit signs and no entry signs. It is not displayed for no overtaking signs and speed limit with supplemental signs.*

        Tech Tips

        *: No entry signs have higher priority than speed limit signs.

        B002AY3E01
        Text in Illustration
        *a Speed Limit or No Entry Related *b Multiple Road Signs Recognized
        *c The illustration shown is an example only. The illustration may differ from the actual vehicle screen. - -

      6. When there is a malfunction in the RSA system or the system is temporarily unusable, a warning message is displayed on the multi-information display, the master warning light illuminates and the multi buzzer sounds.

        Condition Multi-information Display*1 Master Warning Light Multi Buzzer
        System malfunction B002B21 Illuminates Sounds

        Forward recognition camera is temporarily malfunctioning


        • Forward recognition camera voltage is abnormal

        • Forward recognition camera temperature is outside of operating range

        • Other malfunction exists in forward recognition camera

        		 B002AXF - -
        Forward recognition camera lens or windshield glass is dirty. B002B0H - -

        • *: These illustrations are examples.

    2. Headup Display (Models with Headup Display)


      1. Speed limit or no entry related by the forward recognition camera are displayed on the headup display.

        B002AYQE01
        Text in Illustration
        *a Speed Limit or No Entry Related *b The illustration shown is an example only. The illustration may differ from the actual vehicle screen.

  6. DIAGNOSIS


    1. If a malfunction is detected in the RSA system the forward recognition camera cancels the RSA system, sounds the multi buzzer in the combination meter assembly, 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). When a Global TechStream (GTS) is connected to the DLC3, the DTC can be read. For details, refer to the Repair Manual.