2017 SUBARU LEGACY Driving Assist Manual

54
Lane Keep Assist
The stereo cameras detect lane markings
(including Botts’ dots) of the lane and the sys-
tem assists the steering operation by working
with the electric power steering to help keep
your vehicle in its lane when driving on
expressways, freeways and interstate high-
ways.
WARNING
Lane Keep Assist is not an automatic driving system.
Do not overestimate the capabilities of Lane Keep Assist. It is not a sys-
tem to assist inattentive driving or meant to permit driving without hold-
ing the steering wheel. Make sure to grip the steering wheel while
driving. To drive safely, check the distance from the vehicle in front or
from a vehicle driving in parallel with your vehicle, the surrounding con-
ditions and the surrounding environment while driving.
If you feel that the level of control and timing by the system are different from
your own driving style, the system may not support safe driving. Do not use
Lane Keep Assist.
Lane Keep Assist does not always operate under all situations. If you rely
only on the Lane Keep Assist to stay in a lane, it may cause an accident such
as a collision with an obstacle beside your lane or with a vehicle driving in an
adjacent lane.x Check that there are no problems with the tires and brakes during a daily
inspection before using the system.
Ÿ Refer to “Warranty and Maintenance Booklet”.
x The system may not operate properly under the following conditions. Do
not use Lane Keep Assist.
- The air pressure of tires is not to specification.
*1
- Tires that are unevenly worn or tires with uneven wear patterns are installed.*1
- Tires that are the wrong size are installed.*1
- The wheel balance is abnormal (e.g., the balance weight is removed ormisaligned.)*1
- The wheel alignment is out of the specified value.*1
- Flat tires have been fixed temporarily with a tire repair kit.
- The suspension has been modified (including genuine SUBARU parts).
S02069
Lane
markings

Lane Keep Assist
55
Continued on next pageŸ
- Any object that disturbs the stereo cameras’ view is installed on the vehi-
cle.
- Tire chains are installed.
- When you feel an abnormal vibration in the steering wheel or feel the steering wheel is heavier than usual.
- The steering wheel has been replaced with parts other than genuine SUBARU parts.
- The headlights are dirty or they have snow, ice or dirt on them. (Objects are not adequately illuminated and are difficult to detect.)
- The headlights are not aligned correctly. (Objects are not adequately illu- minated and are difficult to detect.)
- The headlights and fog lamps, and other lights, have been modified.
- Vehicle operation has become compromised due to an accident or mal- function.
- The brake system warning light (red) is illuminated.
- A heavy cargo is loaded onto or inside the vehicle.
- The maximum number of occupants is exceeded.
- Your vehicle is towing a vehicle, etc.
- There is something wrong with the combination meter. For example, an indicator light or a warning light in the combination meter does not prop-
erly turn on or off, a beep does not sound, or the indication on the liquid-
crystal display is different from when it is normal.
*2
*1: The wheels and tires have critically important functions. Be sure to
use the appropriate ones.
For details, refer to the Owner’s Manual for your vehicle.
*2: For details about the functions and operations of the combination meter, refer to the Owner’s Manual for your vehicle.
x Lane Keep Assist is designed for use on expressways, freeways, toll
roads, interstate highways and similar limited access roads. In the follow-
ing conditions, do not use Lane Keep Assist. Doing so may result in an
accident.
- Ordinary roads (roads other than those mentioned above)
- Roads with sharp curves
- Roads with lane restric- tions or tentative lanes due
to construction work, etc.
- Old lane markings remain.
- Snow, puddles or snow melting agents remain on
the road surface.
- Cracks or constructed traces remain on the road
surface.
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Lane Keep Assist
56
ŸContinued from previous page
- Frozen roads, snow-covered roads or other slippery road surfaces
The tires may spin, causing loss of control of the vehicle.
- When entering a sharp curve into an interchange or junction, or a service area, parking area, toll booth or other facilities.
- When there are changes in brightness, such as at a tunnel entrance or exit.
- When visibility is poor due to sand, smoke or water vapor blowing in the wind, or when the vehicle in front or oncoming traffic causes water,
snow, dirt or dust to obscure the view.
- When there is snow, frost, dirt or dust on the windshield or it is clouded.
- When water droplets from rain or dirt have not been fully wiped off on the windshield.
It may not be possible to detect the lane, making correct control impossi-
ble.
- When the stereo cameras’ field of view is obstructed (for example by a canoe on the roof of the vehicle).
- The stereo cameras may have difficulty detecting the objects under the following conditions and the system may not operate properly.
- When driving at night or in a tunnel without the headlights on.
- When light is poor in the evening or early morning.
- In bad weather (for example, rain or snow)
- The distance between your vehicle and the vehicle in front is short, mak- ing it difficult to detect lane markings.
- When a vehicle intruded from an adjacent lane or the vehicle in front changed lanes.
- The shape of a curve in the road suddenly changes.
- Shadows of guardrails or similar objects are overlapped on the lane markings.
- When your vehicle is exposed to a strong light from the front (backlight from the sun, headlights, etc.).
- The width of a lane is narrow.
- The stereo cameras may have difficulty detecting the lane due to the per- formance of the cameras.
xThere are no lane markings or they are very worn.
x The lane markings are painted in yellow.
x It is difficult to detect lane markings because they are similar in color to
the road surface.
x The lane markings are drawn in double.
x The width of lane markings is narrow.
x The indicated lines for the area are touched to walls and poles.
- The shape of lane markings suddenly changes (entrance/exit of a curve, crank and S-shaped road, etc.).
- There is curb or side wall in the road shoulder.
- The brightness changes such as when you drive under an overpass.

Lane Keep Assist
57
CAUTION
xThe performance of Lane Keep Assist may not be optimal under the following
conditions. In addition, Lane Keep Assist may not operate or the operation
may be canceled.
- Immediately after the weight of your vehicle changes radically
- Immediately after the replacement of a tire or the adjustment of tire pres- sure
- Immediately after the adjustment, repair or replacement of cameras or related components
- Immediately after the repair or replacement of the suspension or steering system
- A winter tire or a tire other than a genuine SUBARU tire is used.
- The vehicle is in a crosswind.
- The road grade abruptly changes (uphill or downhill).
- The grade of the crossing direction in a road is large or changes abruptly.
- Unevenness, winding and joint of a road surface
- The acceleration/deceleration is high.
- Immediately after starting the engine when the outside temperature is low.
- The outside temperature is high.
x When you do not use Lane Keep Assist, make sure to turn off the (Lane
Keep Assist) switch. If you turn it on, the function may operate unexpectedly,
causing an accident.
x If you turn on the (Lane Keep Assist) switch, the operation power of
electric power steering may change.

Lane Keep Assist
58
The system detects lane markings in order to help prevent departure from the lane. If you
drive on expressways, freeways or interstate highways at speeds above approximately 40
MPH (65 km/h) and the vehicle is about to depart from the lane, the system assists the
steering operation by turning it to the direction that will help prevent the lane departure.
■How to use Lane Departure Prevention Function
Press the (Lane Keep Assist) switch.
Lane Keep Assist is turned on, and “ ” (Lane Keep Assist indicator) (white) is displayed
on the EyeSight display area of the multi information display.
Lane Departure Prevention Function
S02043
There is a strong
possibility of lane
departure. There is a
possibility of lane
departure.
S01994milesA
MPG
S02044
Lane Keep
Assist indicator
(white)

Lane Keep Assist
59
Press the (Lane Keep Assist) switch once again to turn it off, and “ ” (Lane Keep
Assist indicator) is turned off on the EyeSight display area.
The Lane Departure Prevention Function goes into the standby status, and the lane indica-
tor illuminates when all of the following conditions are met.x The vehicle speed is between approximately 40 MPH (65 km/h) and 90 MPH (145 km/h).
x The system is detecting the lane markings.
x The driver is holding the steering wheel.
x When driving on a road that has a lane width that is between approximately 10 ft (3 m)
and 15 ft (4.5 m).
x When driving on a straight road or gentle curve.
x When driving near the center of a lane.
When the vehicle is about to depart from the lane, Lane Departure Prevention Function
starts to operate and “ ” (Lane Keep Assist indicator) illuminates in green while it is
operating.
NOTE
x If you just lightly put your hands on the steering wheel for a certain period
of time or if you do not operate the steering wheel, the function will auto-
matically be canceled. (“ ” Lane Keep Assist indicator) illuminates in
white again.)
x Lane Departure Prevention Function operates when the system deter-
mines that the vehicle will depart from the lane if you continue to drive in
the same manner. Therefore, it operates at an earlier timing than Lane
Departure Warning (
Ÿ Refer to page 68.) (it may depend on the surround-
ing environment and road condition).
x The lane indicator in the standby status and in operation may illuminate
only on the left side or right side.
milesA
MPG
milesA
MPG
milesA
MPG
S02045
Lane Keep
Assist
indicator
(white)
Turned on Standby status In operation
(white) (green)

Lane Keep Assist
60
■Canceling Lane Departure Prevention Function
●
Cancellation by the operation of a driver (In case no beep sounds)
The following operation cancels Lane Departure Prevention Function.
If the function is canceled, “ ” (Lane Keep Assist indicator) and the lane indicator are
turned off on the EyeSight display area. x Press the (Lane Keep Assist) switch.
Either of the following operations temporarily cancels the Lane Departure Prevention Function.
While temporarily canceling the function, “ ” (Lane Keep Assist indicator) on the
EyeSight display area illuminates in white and the lane indicator is turned off. x Depressing the brake pedal
x Operating the turn signal lever
x When the system determines that the driver operates the steering wheel to make a lane
change.
x Turning on the hazard warning flasher switch
●Automatic cancellation by the system (An audible beep will sound.)
Under the following conditions, a beep sounds and the Lane Departure Prevention Function
is temporarily canceled.
While the function is temporarily canceled, “ ” (Lane Keep Assist indicator) on the
EyeSight display area illuminates in white and the lane indicator is turned off.
x When the system cannot detect the lane.
x The windshield wiper operates at a high speed.
x The vehicle speed is less than approximately 37 MPH (60 km/h) or is more than approxi-
mately 93 MPH (150 km/h).
x The ABS, the Vehicle Dynamics Control or the Traction Control System operates.
x Either the driver’s door, the front passenger’s door or the rear door is open.
x The seatbelt of driver’s seat is unfastened.
x The electronic parking brake is applied (The electric parking brake indicator light illumi-
nates or blinks).
x The select lever is shifted to a position other than or position.
x The system could not detect the steering
operation by the driver for a certain period of
time.
- When the system detected no steering operation, the interruption screen appears
on the multi information display. The inter-
ruption screen continues to appear until
the system detects the steering operation.
If the system still cannot detect the steer-
ing operation, the Lane Departure Preven-
tion Function is automatically canceled.
DM
milesA
MPG
Keep Hands OnSteering Wheel
S02046

Lane Keep Assist
61
xWhen entering a sharp curve.
x When driving on a sharp curve.
x When the system determines that the steering assistance is difficult to continue due to the
road condition.
x When the system determines that the steering assistance is difficult to operate due to
another system.
x When the EyeSight system is temporarily stopped. (“ ” (EyeSight Temporary Stop
indicator: White) is turned on.)
Ÿ Refer to page 86.
x When the EyeSight system has a malfunction. (“ ” (EyeSight Warning indicator:
Yellow) is turned on.)
Ÿ Refer to page 87.
NOTE
If the function is automatically canceled during the standby status (“ ”
(Lane Keep Assist indicator) illuminates in white), no beep sounds.