LANE-KEEPING ASSIST SYSTEM SYSTEM DESCRIPTION

LANE-KEEPING ASSIST DESCRIPTION

1. The lane-keeping assist system uses the lane recognition camera sensor's image of the road in front to detect the lane marker on either side of the vehicle. If the system detects that the vehicle is about to move outside of the lane marker, it uses the warning buzzer and multi-information display to warn the driver.

   However, in the following conditions, the lane-keeping assist system may not function normally.

   
   

   • Vehicle is near toll booths or similar areas

   • Road has no lane marker

   • Lane marker is cracked

   • Road has yellow lines

   • There is a shadow on either of the lane markers

   • As a result of reflections, the road surface is bright

   • Road has a reflective surface similar to concrete road

   • Area where brightness changes suddenly, such as entrances and exits of tunnels or similar areas

   • Bright light is directed at the sensor

   • Incline of the road varies, winding road or other type of road where road surface is irregular

   • Bad weather

   • Frozen or snowy roads

   • With water or other liquid on road surface

SYSTEM OPERATION

1. Lane departure warning function:

   The lane departure warning function operates when the lane-keeping assist main switch is on, the vehicle speed is 50 km/h (31 mph) or more, and lane markers on the road surface are detected. With the lane departure warning function operating, if the vehicle is about to move out of the lane and this is detected by the driving support ECU, the ECU uses the warning buzzer and multi-information display to warn the driver. Also, the ECU uses the electronic power steering system's motor to apply steering force and give suggestions to the driver for lane departure avoidance.

   Tech Tips

   This function only provides suggestions for lane departure avoidance. This function does not automatically move the vehicle within a lane.

2. Lane-keeping assist function:

   The lane-keeping assist function operates when the lane-keeping assist main switch is on, the vehicle speed is approximately 75 to 180 km/h (45 to 106 mph), and the dynamic radar cruise control system is on. With the lane-keeping assist function operating, steering assistance is provided for the driver according to the driving conditions so that the vehicle stays near the midpoint of a lane. When the vehicle cannot be maintained within a lane and this is detected by the driving support ECU, the ECU uses the warning buzzer and multi-information display to warn the driver. During the lane-keeping assist function operation, if any of the following conditions occur, the lane-keeping assist function will stop operating. If the condition is no longer detected, the lane-keeping assist function will automatically start operating again.

   Lane-keeping Assist Function Operation Stop Condition	Restart Condition
   Lane recognition camera sensor cannot detect lane marker	Lane recognition camera sensor can detect lane marker
   Vehicle speed is not within 75 to 180 km/h (45 to 106 mph)	Vehicle speed is within 75 to 180 km/h (45 to 106 mph)
   Turn signal light switch is operated	Turn signal light switch is turned off
   Windshield wiper switch is set to Lo or Hi	Windshield wiper switch is turned off
   Steering force above a specified amount is applied	Steering force above specified amount is not detected
   Steering force above a specified amount does not occur*	Steering operation is detected
   Lane change is performed	Driving within a lane is confirmed

   Tech Tips

   *: This refers to situations where the vehicle is driven for 15 seconds or more on a lane that is straight, or 5 seconds or more on a curved road (curve radius 1000 m [3281 ft.] or less).

3. During the lane-keeping assist function operation, if any of the following conditions is detected, the lane-keeping assist function will stop operating.

   
   

   • Dynamic radar cruise control system is canceled*

   • Lane-keeping assist main switch is turned off

   • Lane recognition camera sensor's interior temperature is 65°C (149°F) or more

   • Electronic power steering system's operation limit is reached

   • Lane-keeping assist system is malfunctioning

     Tech Tips

     *: During the lane-keeping assist function operation, if the dynamic radar cruise control system is canceled, the lane-keeping assist system will change from the lane-keeping assist function to the lane departure warning function.

FUNCTION OF MAIN COMPONENTS