2011 Lexus IS220d brake

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CAUTION
Conditions under which the vehicle-to-vehicle distance control may not
function correctly
Apply the brakes as necessary in the following conditions as the radar sen-
sor may not be able to correctly detect vehicles ahead, and a fatal or serious
accident may result:
When water or snow thrown up by the surrounding vehicles hinders the
functioning of the sensor
When your vehicle is pointing upwards (caused by a heavy load in the
trunk etc.)
When the road curves or when the lanes are narrow
When steering wheel operation or your position in the lane is unstable
When the vehicle ahead of you decelerates suddenly
Handling the radar sensor
Observe the following to ensure the cruise control system can function
effectively.
Otherwise, the system may not function correctly and could result in an
accident.
Keep the sensor and front grille cover clean at all times.
Clean the sensor and front grille cover with a soft cloth so you do not
mark or damage them.
Do not subject the sensor or surrounding area to a strong impact.
If the sensor moves even slightly off position, the system may malfunc-
tion. If the sensor or surrounding area is subject to a strong impact, always
have the area inspected and adjusted by any authorized Lexus dealer or
repairer, or another duly qualified and equipped professional.
Do not disassemble the sensor.
Do not attach accessories or stickers to the sensor, grille cover or sur-
rounding area.
Do not modify or paint the sensor and grille cover.
Do not replace them with non-genuine parts.

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Sensor detection information
Certain vehicle conditions and the surrounding environment may affect
the ability of the sensor to correctly detect obstacles. Particular instances
where this may occur are listed below.
• There is dirt, snow or ice on the sensor.
• The sensor is frozen.
• The sensor is covered in any way.
• The vehicle is leaning considerably to one side.
• On an extremely bumpy road, on an incline, on gravel, or on grass.
• The vicinity of the vehicle is noisy due to vehicle horns, motorcycle
engines, air brakes of large vehicles, or other loud noises producing
ultrasonic waves.
• There is another vehicle equipped with parking assist sensors in the
vicinity.
• The sensor is coated with a sheet of spray or heavy rain.
• The vehicle is equipped with a fender pole or wireless antenna.
• Towing eyelets are installed.
• The bumper or sensor receives a strong impact.
• The vehicle is approaching a tall or curved curb.
• In harsh sunlight or intense cold weather.
In addition to the examples above, there are instances in which, because of
their shapes, signs and other objects may be judged by the sensor to be
closer than they are.
The shape of the obstacle may prevent the sensor from detecting it. Pay
particular attention to the following obstacles.
• Wires, fences, ropes etc.
• Cotton, snow and other materials that absorb radio waves
• Sharply-angled objects
•Low obstacles
• Tall obstacles with upper sections projecting outwards in the direction
of your vehicle
If the display flashes and a message is displayed
P. 4 7 3
Customization that can be configured at any authorized Lexus dealer or
repairer, or another duly qualified and equipped professional
Settings (e.g. buzzer volume) can be changed. (Customizable features P.
556)

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Driving assist systems
To help enhance driving safety and performance, the following sys-
tems operate automatically in response to various driving situations.
Be aware, however, that these systems are supplementary and should
not be relied upon too heavily when operating the vehicle.
ABS (Anti-lock Brake System)
Helps to prevent wheel lock when the brakes are applied suddenly,
or if the brakes are applied while driving on a slippery road surface.
Brake assist
Generates an increased level of braking force after the brake pedal
is depressed, when the system detects a panic stop situation.
VSC (Vehicle Stability Control)
Helps the driver to control skidding when swerving suddenly or
turning on slippery road surfaces.
TRC (Traction Control)
Maintains drive power and prevents the rear wheels from spinning
when starting the vehicle or accelerating on slippery roads.
Hill-start assist control (vehicles with an automatic transmis-
sion)
Helps to prevent the vehicle from rolling backward when starting
on an incline or slippery slope.
EPS (Electric Power Steering)
Employs an electric motor to reduce the amount of effort needed to
turn the steering wheel.
PCS (Pre-Crash Safety System) (if equipped)
P. 230
VDIM (Vehicle Dynamics Integrated Management)
Provides integrated control of the ABS, brake assist, TRC, VSC,
hill-start assist control, and EPS systems.
Helps to maintain vehicle stability when swerving on slippery road

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Sounds and vibrations caused by the ABS, brake assist, VSC, TRC and hill-
start assist control systems
A sound may be heard from the engine compartment if the brake pedal is
depressed repeatedly when the engine is started or just after the vehicle
begins to move. This sound does not indicate that a malfunction has
occurred in any of these systems.
Any of the following conditions may occur when the above systems are
operating. None of these indicates that a malfunction has occurred.
• Vibrations may be felt through the vehicle body and steering.
• A motor sound may be heard after the vehicle comes to a stop.
• The brake pedal may pulsate slightly when the ABS is activated.
• The brake pedal may move down slightly after the ABS is activated.
Hill-start assist control is operational when
The shift lever is in the D or S position.
The brake pedal is not depressed.
The vehicle rolls backward.
EPS operation sound
When the steering wheel operates, a motor sound (whirring sound) may be
heard. This does not indicate a malfunction.
Reduced effectiveness of EPS
The effectiveness of EPS is reduced to prevent the system from overheating
when there is frequent steering input over an extended period of time. The
steering wheel may feel heavy as a result. Should this occur, refrain from
excessive steering input or stop the vehicle and turn the engine OFF. The
system should return to normal within 10 minutes.
If the slip indicator comes on
It may indicate a malfunction in the VSC, TRC or hill start assist control
function. Contact any authorized Lexus dealer or repairer, or another duly
qualified and equipped professional.

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PCS (Pre-Crash Safety system)
When the radar sensor detects possibility of a frontal collision, the pre-
crash safety system such as the brakes and seat belts are automatically
engaged to lessen impact and injuries to occupants as well as vehicle
damage.
Pre-crash seat belts
If the pre-crash sensor detects that a collision is unavoidable, the
pre-crash safety system will retract the seat belt before the collision
occurs.
The same will happen if the driver makes an emergency braking or
loses control of the vehicle. (P. 7 6 )
However, the system will not operate in the event of skidding when
the VSC systems are disabled.
Pre-crash brake assist
When there is a high possibility of a frontal collision, the system
applies greater braking force in relation to how strongly the brake
pedal is depressed.
Pre-crash braking
When there is a high possibility of a frontal collision, the system
warns the driver using a warning light, warning display and buzzer.
If the system determines that a collision is unavoidable, the brakes
are automatically applied to reduce the collision speed. The pre-

: If equipped

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Disabling the pre-crash braking
The pre-crash braking function
can be turned on and off using
the satellite switch. (P. 365)
Press “”or “” to display the
PCS brake setting ( ). Then,
press the “ON/OFF” button in
the middle of the switch to
select either “ON” or “OFF”
().
It may take approximately 3
seconds for the display to
change after the satellite switch
is operated.
The “PCS” warning light
flashes when “OFF” is selected.
Radar sensor
Detects vehicles or other obsta-
cles on or near the road ahead
and determines whether a colli-
sion is imminent based on the
position, speed, and heading of
the obstacles.
Grille cover
Radar sensor
Obstacles not detected
The sensor cannot detect plastic obstacles such as pylons. There may also be
occasions when the radar sensor cannot detect pedestrians, animals, bicy-
cles, motorcycles, trees, or snowdrifts.

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The pre-crash safety system is operational when
Pre-crash seat belts (type A):
• Vehicle speed is above 5 km/h (4 mph).
• The speed at which your vehicle is approaching the obstacle or oncom-
ing vehicle exceeds 30 to 40 km/h (19 to 25 mph).
• The front occupants are wearing a seat belt.
Pre-crash seat belts (type B):
• Vehicle speed exceeds 30 km/h (19 mph).
• The system detects sudden braking or skidding.
• The front occupants are wearing a seat belt.
Pre-crash brake assist:
• Vehicle speed is above 30 km/h (19 mph).
• The speed at which your vehicle is approaching the obstacle or the
vehicle running ahead of you is greater than 30 to 40 km/h (19 to 25
mph).
• The brake pedal is depressed.
Pre-crash braking:
• The pre-crash braking function is activated.
• Vehicle speed is above 15 km/h (10 mph).
• The relative speed difference between your vehicle and another vehi-
cle that is forward of your vehicle, or the speed at which your vehicle
is approaching an obstacle is greater than 15 km/h (10 mph).
Conditions that may trigger the system even if there is no possibility of col-
lision
When there is an object by the roadside at the entrance to a curve
When passing an oncoming vehicle on a curve
When driving over a narrow iron bridge
When there is a metal object on the road surface
When driving on an uneven road surface
When passing an oncoming vehicle on a right-turn (right-hand drive
countries) or left-turn (left-hand drive countries)
When your vehicle rapidly closes on the vehicle in front
When a grade separation/interchange, sign, billboard, or other structure
appears to be directly in the vehicle’s line of travel.

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When a billboard or other metallic structure appears to be in the vehi-
cle’s direct line of travel due to driving on a hill.
When an extreme change in vehicle height occurs
When the axis of the radar is out of adjustment
When passing through certain toll gates
When driving on a bridge.
When the system is activated in the situations described above there is also a
possibility that the seat belts will retract quickly and the brakes will be
applied with a force greater than normal. When the seat belt is locked in the
retracted position, stop the vehicle in a safe place, release the seat belt and
refasten.
Situations in which the pre-crash safety system does not function properly
The system may not function effectively in situations such as the following:
On roads with sharp bends or uneven surfaces
If a vehicle suddenly moves in front of your vehicle, such as at an inter-
section
If a vehicle suddenly cuts in front of your vehicle, such as when overtak-
ing
In inclement weather such as heavy rain, fog, snow or sand storms
When your vehicle is skidding with the VSC system off
When an extreme change in vehicle height occurs
When the axis of the radar is out of adjustment
Automatic cancelation of the pre-crash safety system
When a malfunction occurs due to sensor contamination, etc. that results in
the sensors being unable to detect obstacles, the pre-crash safety system will
be automatically disabled. In this case, the system will not activate even if
there is a collision possibility.