AUTOMATIC HIGH BEAM SYSTEM SYSTEM DESCRIPTION


  1. AUTOMATIC HIGH BEAM SYSTEM


    1. General

      The automatic high beam system enhances the illumination of the area in front of the vehicle to improve visibility for the driver. It works by detecting light from the front using the camera built into the pre-crash safety city sensor and turning the high beam headlights on or off automatically.

    2. Function of Main Components

      Component Outline
      Pre-crash Safety City Sensor Determines when to turn the high beams on and off after identifying the lights of oncoming vehicles, preceding vehicles and other lights from the picture information of its camera sensor. Then, it sends high beam request signals to the main body ECU (multiplex network body ECU) via CAN communication.
      Brake Actuator Assembly (Skid Control ECU) Outputs the information about the speed of the right front wheel. This information is used by the pre-crash safety city sensor to turn the high beam headlights on and off.
      Combination Meter Assembly

      Turns on the automatic high beam indicator light and displays a message on the multi-information display based on an indicator illumination request signal from the main body ECU (multiplex network body ECU).

      Tech Tips


      • When an automatic high beam system malfunction is detected, the automatic high beam indicator light turns off and "Headlight System Malfunction Visit Your Dealer" is displayed on the multi-information display.

      • The automatic high beam indicator light illuminates to inform the driver when the automatic high beam system is active.
      Main Body ECU (Multiplex Network Body ECU)

      • Determines whether the automatic high beam system is in standby mode based on a dimmer switch high position signal and light control switch AUTO position signal and sends an indicator illumination request signal and message display request signal to the combination meter assembly. These are used to put the automatic high beam system in stanby mode.

      • Receives the high beam illumination request signal from the lane departure warning camera and changes between the high beam headlights and low beam headlights.

      • Performs illumination control for the automatic high beam system and stores Diagnostic Trouble Codes (DTCs) when the system malfunctions.

    3. Basic Function


      1. When all of the following conditions are met, the automatic high beam system is activated and the automatic high beam indicator light turns on:


        • The ignition switch is ON.

        • The light control switch is in the AUTO position and the low beam headlights are on.

        • The dimmer switch is in the high position.

      2. When all of the following conditions are met, the high beam headlights automatically turn on after a short delay:


        • Vehicle speed is more than approximately 34 km/h (21 mph).

        • The area in front of the vehicle is dark.

        • There are no oncoming vehicles with headlights on.

        • There are no preceding vehicles with taillights on.

        • There are few streetlights along the street ahead.

      3. When any of the following conditions are met, the high beam headlights automatically turn off after a short delay:


        • Vehicle speed is less than 27 km/h (17 mph).

        • The level of ambient light is higher than a specified threshold.

        • There are oncoming vehicles with headlights on.

        • There are preceding vehicles with taillights on.

        • Light from streetlights ahead is higher than a specified threshold.

      4. When any of the following conditions are met, the automatic high beam system will be canceled and the indicator light will turn off.


        • The ignition switch is turned off.

        • The light control switch is turned to any position except the AUTO position.

        • The low beam headlights are turned off.

        • The dimmer switch is moved to the low position.

        Tech Tips

        It is possible to manually turn the high beam headlights on and off using either of the following operations:


        • Turn the light control switch from the AUTO position to the head position. The high beam headlights will turn on according to the dimmer switch high position. To change to the low beam headlights, move the dimmer switch to the low position.

        • Move the dimmer switch from the high position to the low position. The low beam headlights will turn on according to the dimmer switch position.

        Tech Tips

        The automatic high beam system monitors the area in front of the vehicle using the pre-crash safety city sensor and makes a judgment to turn the high beam headlights on when the surrounding area is dark (there are no headlights from oncoming vehicles and no taillights from preceding vehicles). High beam control limitations:


        • When the surrounding area is not dark enough, the high beam headlights will not turn on even if the low beam headlights are turned on by the automatic light control system and the automatic high beam indicator light on the combination meter assembly is illuminated. (The light level sufficient to turn the auto low beam headlights on is not the same as the light level required to automatically change the low beam headlights to high beam headlights.)

        • When an oncoming vehicle suddenly appears at a sharp curve or a vehicle crosses the path of the vehicle, the high beam headlights may remain on.

        • When the fog lights of an oncoming vehicle are detected, the high beam headlights may be turned off.

        • The timing of the high beam headlights turning on and off may differ depending on the brightness of headlights or fog lights from oncoming vehicles or the taillights of preceding vehicles.

        • The timing of the high beam headlights turning on and off may differ between normal conditions (good weather) and when driving on wet, frozen or snowy roads.

        • The timing of the high beam headlights turning on and off may differ depending on the number of occupants and amount of cargo present.

        • Be aware that on some occasions, the high beam headlights may switch on and off unexpectedly.

        Tech Tips

        The pre-crash safety city sensor continually monitors the light level in the area to the front of the vehicle. There is a delay in turning on the high beam headlights. Even when there is no ambient light, the high beam headlights will not turn on immediately. The delay will vary depending on the situation.