OUTLINE
The lane-keeping assist system uses a lane recognition camera sensor to detect lane markers on the road surface, assists the driver's steering operation by using Electric Power Steering (EPS), and activates the lane departure warning when needed.
The lane-keeping assist system is controlled by the driving support ECU.
PRECAUTION
General Handling Precautions
Use lane-keeping assist on freeways or expressways with clear lane markers.
Do not rely entirely on lane-keeping assist. This system only assists the steering operation to help keep the vehicle within the lane. The driver is required to operate the steering wheel to correct the vehicle path while paying attention to road conditions and traffic.
The lane departure warning function alerts the driver to unintentional deviation from the lane. It does not aim to assist the steering operation while the driver releases the steering wheel or does not pay attention to the road ahead.
The lane-keeping assist applies an appropriate amount of steering assist in accordance with driving conditions to help keep the vehicle in the lane. It does not aim to assist the steering operation if the driver releases the steering wheel or does not pay attention to the road ahead.
When the driver turns the steering wheel during lane-keeping assist operation, lane-keeping assist is suspended and the driver steering control is prioritized.
Do not place any objects on the instrument panel. The system may mistakenly recognize an object reflected in the windshield glass as lane marker.
Keep the windshield glass clean where the lane recognition camera sensor is mounted. The lane recognition camera sensor performance may be affected if dirt, raindrops, condensation, or snow is on the windshield glass.
Do not attach stickers or labels, nor affix any ornaments to the windshield glass.
Set the inner rear view mirror to face the proper direction. Otherwise, it may block the lane recognition camera sensor and lane markers may not be detected accurately.
Do not touch the lane recognition camera sensor's lens. Fingerprints left on the lens may cause inaccurate detection or non-detection and lane markers may not be detected accurately.
Do not remove the lane recognition camera sensor. Since the lane recognition camera sensor angle is precisely adjusted, angle adjustment must be performed after the lane recognition camera sensor is reinstalled, otherwise the lane recognition camera sensor may not recognize lane markers properly.
Do not subject the lane recognition camera sensor to strong forces.
When the brake pedal is depressed or the turn signal is detected during lane-keeping assist operation, lane-keeping assist is suspended.
When the system detects a fault during lane-keeping assist operation when the vehicle speed is equal to or greater than approximately 50 km/h (31 mph)*1 or 48 km/h (30 mph)*2, the multi buzzer sounds, LKA main indicator light turns off, "CHECK LKA SYSTEM" appears on the multi-information display, and lane-keeping assist stops operating.
Since this does not interrupt normal driving, keep driving carefully.
When the engine is stopped and started again and the LKA main switch is turned on, lane-keeping assist can be resumed if the system returns to normal.
In some cases, lane-keeping assist resumes when the LKA main switch is turned off and back to on and the system returns to normal.
If the LKA main indicator light turns off when the vehicle speed is equal to or greater than approximately 50 km/h (31 mph)*1 or 48 km/h (30 mph)*2, even though these operations are completed, the system is malfunctioning. Contact a Toyota dealer.
Trailer towing may lead to performance decline.
Changing tires (including changing to studless tires) or changing suspension parts may lead to a decline in performance.
*1: Except models for Britain
*2: Models for Britain
Precautions Concerning Road Conditions
If the system cannot recognize lane markers under the following conditions, the system does not operate.
No lane markers on roads, for example, before tollgates
Unclear lane markers
One of the lane markers is in the shade
The road surface reflects the bright sunlight
The road surface is a bright color, for example, concrete roads
Brightness changes suddenly, for example, tunnel entrances or exits
In backlight
Roads where gradient changes, on winding roads or on uneven road surfaces
In bad weather
Ice, snow or water puddles on roads
Steering assist force may be mistakenly applied or the system does not operate due to lane markers being recognized incorrectly under the following conditions:
Snow remains in ruts
With roads wet due to rain, street lights or headlights of an oncoming vehicle are reflected on the road surface in the shape of lines
Shadows are on road surfaces almost parallel to lane markers
Guardrails or curbstones are along roads
Section of road with asphalt repair marks
Repaired road section in which old lane markers can still be seen
Reflection from headlights of oncoming vehicles onto the lane recognition camera sensor
Branch roads or intersections
If the distance between vehicles is extremely short, lane markers may not be recognized correctly. Maintain an appropriate distance between vehicles.
When the vehicle is parked during hot weather, the system will not operate for a while after the vehicle starts running. When the temperature in the cabin reaches the appropriate level at which the lane recognition camera sensor can operate, the system can be resumed by turning off the LKA main switch, waiting a moment, and turning it on again.
Precautions for Lane Departure Warning Function
Keep the vehicle in the lane by turning the steering wheel appropriately and drive carefully.
The lane departure warning function does not prevent lane deviation. It only alerts the driver to lane deviation by displaying a warning message, sounding a buzzer, and briefly applying a small counter-steering force.
When the alarm is activated, operate the steering wheel appropriately to guide the vehicle back into the lane.
The alarm can be activated while the vehicle is running between approximately 50 km/h (31 mph) and 200 km/h (124 mph).*1
The alarm can be activated while the vehicle is running between approximately 48 km/h (30 mph) and 200 km/h (124 mph).*2
*1: Except models for Britain
*2: Models for Britain
The alarm may be activated early or may not be activated depending on conditions around the vehicle. The driver is required to operate the steering wheel to correct the vehicle path while paying attention to road conditions and traffic.
When there are any strip-shaped patterns, such as shades, ruts or blurred lane markers that are no longer used on the road, the system may mistakenly recognize them as lane markers. Turn the LKA main switch off under such road surface conditions.
The alarm is not activated if driver steering force is detected.
When the alarm is activated, the steering wheel return feeling or vehicle movement varies depending on the driving conditions (such as road gradient and wind conditions).
Precautions for Lane-keeping Assist Function
Always place both hands on the steering wheel, and drive carefully.
The lane-keeping assist applies an appropriate amount of steering assist to help keep the vehicle in the lane. The lane-keeping assist does not automatically guide the vehicle to the center of the lane.
When a crosswind blows, a cross slope is reached, or the vehicle is turning a corner, the lane-keeping assist function may not operate properly.
When the steering wheel is not operated for a certain period, the multi buzzer in the combination meter assembly sounds, the multi-information display indicates a message, and the lane-keeping assist function is suspended (approximately 15 seconds on straight roads, and approximately 5 seconds on curved roads).
When there are any strip-shaped patterns, such as shades, ruts or blurred lane markers that are no longer used on the road, turn the LKA main switch off. If the system recognizes them as lane markers, incorrect steering assist force may be applied.
Since the function may be suspended or stop operating under the following conditions, always place both hands on the steering wheel, check the multi-information display message and drive carefully.
Lane markers are unclear (the function is suspended).
The system malfunction is detected (the function stops operating).
When the dynamic radar cruise control system is canceled, the lane-keeping assist function is suspended and the lane departure warning function is activated.
When the vehicle speed is approximately 72 km/h (45 mph) or less, or approximately 170 km/h (106 mph) or more, the lane-keeping assist function is suspended and the lane departure warning function is activated.
When the vehicle speed reaches between approximately 72 km/h (45 mph) and 170 km/h (106 mph), the system changes to the lane-keeping assist function.