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CAUTION
Before using dynamic radar cruise control
Do not overly rely on vehicle-to-vehicle distance control.
Be aware of the set speed. If automatic deceleration/acceleration is not
appropriate, adjust the vehicle speed, as well as the distance between your
vehicle and vehicles ahead by applying the brakes etc.
Cautions regarding the driving assist systems
Observe the following precautions.
Failure to do so may cause an accident resulting in death or serious injury.
Assisting the driver to measure following distance
The dynamic radar cruise control is only intended to help the driver in
determining the following distance between the driver’s own vehicle and
a designated vehicle traveling ahead. It is not a mechanism that allows
careless or inattentive driving, and it is not a system that can assist the
driver in low-visibility conditions. It is still necessary for driver to pay
close attention to the vehicle’s surroundings.
Assisting the driver to judge proper following distance
The dynamic radar cruise control determines whether the following dis-
tance between the driver’s own vehicle and a designated vehicle traveling
ahead is appropriate or not. It is not capable of making any other type of
judgement. Therefore, it is absolutely necessary for the driver to remain
vigilant and to determine whether or not there is a possibility of danger in
any given situation.
Assisting the driver to operate the vehicle
The dynamic radar cruise control has no capability to prevent or avoid a
collision with a vehicle traveling ahead. Therefore, if there is ever any
danger, the driver must take immediate and direct control of the vehicle
and act appropriately in order to ensure the safety of all involved.
To avoid inadvertent cruise control activation
Switch the cruise control off using the “ON-OFF” button when not in use.
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CAUTION
Situations unsuitable for dynamic radar cruise control
Do not use dynamic radar cruise control in any of the following situations.
Doing so may result in inappropriate speed control and could cause an acci-
dent resulting in death or serious injury.
In heavy traffic
On roads with sharp bends
On winding roads
On slippery roads, such as those covered with rain, ice and snow
On steep downhills, or where there are sudden changes between sharp up
and down gradients
At entrances to expressways
When weather conditions are bad enough that they may prevent the sen-
sors from functioning correctly (fog, snow, sandstorm, heavy rain, etc.)
Vehicle speed may exceed the set speed when driving down a steep hill.
When an approach warning buzzer is heard often
When your vehicle is towing a trailer or during emergency towing
When the sensor may not be correctly detecting the vehicle ahead
Apply the brakes as necessary when any of the following types of vehicles
are in front of you.
As the sensor may not be able to correctly detect these types of vehicles, the
approach warning (P. 208) will not be activated, and a fatal or serious
accident may result.
Vehicles that cut in suddenly
Vehicles traveling at low speeds
Vehicles that are not moving
Vehicles with small rear ends (trailers with no load on board etc.)
Motorcycles traveling in the same lane
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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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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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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.
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When driving
IS250/220d/200d_EEImportant points regarding turning
The wheels of the trailer will travel closer to the inside of the
curve than the wheels of the vehicle. To make allowance for this,
take the turns wider than you would normally.
Important points regarding stability
Vehicle movement resulting from uneven road surfaces and
strong crosswinds will affect handling. The vehicle may also be
rocked by passing buses or large trucks. Frequently check
behind when moving alongside such vehicles. As soon as such
vehicle movement occurs, immediately start to decelerate
smoothly by slowly applying the brakes. Always steer the vehi-
cle straight ahead while braking.
Passing other vehicles
Consider the total combined length of your vehicle and trailer
and ensure that the vehicle-to-vehicle distance is sufficient
before executing lane changes.
Transmission information
Refrain from driving in 6 (manual transmission) or 4 range in S
mode (automatic transmission) to maintain the effectiveness of
the engine brake and the charge performance of electrical com-
ponents.
If the engine overheats...
Towing a loaded trailer up a long steep incline in temperatures
exceeding 30C (85F) may result in the engine overheating. If
the engine coolant temperature gauge indicates that the engine is
overheating, turn the air conditioning off immediately, leave the
road and stop the vehicle in a safe place. (P. 525)
When parking the vehicle
Always place wheel chocks under the wheels of both the vehicle
and trailer. Firmly set the parking brake and shift the shift lever
to P for automatic transmissions, and 1 or R for manual trans-
missions.