cruise control Lexus IS250 2010 User Guide

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IS350/250_U
Dynamic radar cruise control∗
Dynamic radar cruise control supplements conventional cruise control
with a vehicle-to-vehicle distance co ntrol. In the vehicle-to-vehicle dis-
tance control mode, the vehicle automatically accelerates or decelerates
in order to help to maintain a set following distance from vehicles ahead.
Indicator
Display
Distance switch
Cruise control switch
∗: If equipped

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■Selecting cruise mode
Selecting vehicle-to-vehicle dis-
tance control mode
Turn the “ON-OFF” button
on.
Push the button once more to
deactivate.
Selecting conventional con-
stant speed control mode Turn the “ON-OFF” button
on.
Push the button once more to
deactivate.
Vehicle-to-vehicle distance con-
trol mode is always reset when
the “ENGINE START STOP”
switch is switched to IGNITION
ON mode.
Switch to constant speed
control mode.
(Push and hold for approxi-
mately one second.)

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■Driving in the selected cruise control mode
Accelerate or decelerate to the
desired speed and press the
lever down to set.
■ Adjusting the speed setting
Increase speed
Decrease speed
Hold the lever until the desired
speed setting is displayed.
Fine adjustment of the set speed
can be made by lightly pressing
the lever up or down and releas-
ing it. Adjustment can be made
in increments of approximately
1.0 mph (1.6 km/h) when in the
constant speed control mode,
and approximately 5.0 mph or
5.0 km/h when in vehicle-to-
vehicle distance control mode.

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■Canceling and resuming the speed setting
Cancel
Push the lever towards you to
cancel cruise control.
The setting is also canceled
when the brakes are applied.
Resume
To resume cruise control and
return to the set speed, push the
lever up.
■Changing the vehicle- to-vehicle distance
Each push of the switch changes
the vehicle-to-vehicle distance
Long
Medium
Short
The vehicle-to-vehicle distance
is automatically set to the long
mode when the “ENGINE
START STOP” switch is
switched to IGNITION ON
mode.
A mark will be displayed to indi-
cate the presence of the vehicle
if a vehicle is running ahead of
you.
Preceding
vehicle mark

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2-4. Using other driving systems
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The system continues follow-up cruising while adjusting for changes in the
speed of the vehicle ahead in order to maintain the vehicle-to-vehicle dis-
tance set by the driver.
Example of acceleration (when there are no longer vehicles driving
slower than the set speed in the lane ahead): When the speed is set to
62 mph (100 km/h) and the vehicle ahead driving at 50 mph (80
km/h) is out of the lane
When the vehicle ahead of you executes a lane change, the system slowly
accelerates until the set vehicle speed is reached. The system then returns to
fixed speed cruising.
■Dynamic radar cruise control warning lights, messages and buzzers
Warning lights, messages and buzzers are used to indicate a system malfunction or
to alert you to the need for caution while driving. ( →P. 4 8 0 )
■The dynamic radar cruise can be set when
●The shift lever is in the D position or S position. However, it cannot be set if any
of the ranges 1 through 3 has been selected.
●Vehicle speed is more than approximately 30 mph (50 km/h).
■Accelerating
The vehicle can accelerate normally. After acceleration, the set speed resumes.
However, during vehicle-to-vehicle distance control mode, the vehicle speed may
decrease below the set speed in order to maintain the distance to the vehicle
ahead.
■Automatically canceling vehicle-to-vehicle distance control
Vehicle-to-vehicle distance control driving is automatically canceled in the follow-
ing situations.
●Vehicle speed falls below 25 mph (40 km/h)
●VSC is activated
●The sensor cannot operate correctly because it is covered in some way.
●The windshield wipers are operating at high speed.
●The “ECT SNOW” switch is set to snow mode.
If vehicle-to-vehicle distance control driving is automatically canceled for any other
reason, there may be a malfunction in the system. Contact your Lexus dealer.

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IS350/250_U
■Automatically cancelling constant speed control
The set speed is automatically canceled in the following situations.
●Actual vehicle speed is more than 10 mph (16 km/h) below the preset vehicle
speed
At this time, the memorized set speed is not retained.
●Vehicle speed falls below 25 mph (40 km/h)
●VSC is activated
■Vehicle-to-vehicle distance settings
Select a distance from the table below. Note that the distances shown correspond
to a vehicle speed of 50 mph (80 km/h). Vehicle-to-vehicle distance increases/
decreases in accordance with vehicle speed.
■Radar sensor and grille cover
Always keep the sensor and grille cover clean to ensure that the vehicle-to-vehicle
distance control operates properly. (Some obstructions, such as snow, ice or plastic
objects, cannot be detected by the obstruction sensor.)
Dynamic radar cruise control is canceled if an obstruction is detected.
Distance optionsVehicle-to-vehicle distance
LongApproximately 210 ft. (65 m)
MediumApproximately 150 ft. (45 m)
ShortApproximately 100 ft. (30 m)
Grille cover
Radar sensor

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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 vehicle 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 determin-
ing 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 distance
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 deter-
mine 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
Keep the “ON-OFF” button off 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 control of speed and could cause an accident
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 or 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 sensors
from functioning correctly (fog, snow, sandstorm, etc.)
●When a buzzer can be heard often
●When your vehicle is towing a trailer
■When the radar 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 prox-
imity alarm (→P. 480) will not be activated, and an 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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IS350/250_U
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 sensor may
not be able to correctly detect vehicles ahead, and an accident may result.
●When water or snow thrown up by the surrounding vehicles hinders the function-
ing 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:
●Keep the sensor and front grille clean at all times.
Clean the sensor and front grille 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 malfunction. If the
sensor or surrounding area is subject to a strong impact, always have the area
inspected and adjusted by a Lexus dealer.
●Do not disassemble the sensor.
●Do not attach accessories or stickers to the sensor, grille or surrounding area.
●Do not modify or paint the sensor and grille.
■To ensure the radar sensor functions correctly
Do not do the following to the sensor or grille cover as doing so may cause the sen-
sor not to function correctly and could result in an accident.
●Stick or attach anything to them
●Leave them dirty
●Disassemble, or subject them to strong shocks
●Modify or paint them
●Replace them with non-genuine parts

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3-7. Other interior features
IS350/250_U
■Changing the settings
Each item is displayed and its setting can be changed only in the following condi-
tions:
●Intuitive parking assist: When the “ENGINE START STOP” switch is in IGNI-
TION ON mode.
●Items other than the above: When the “ENGINE START STOP” switch is in
IGNITION ON mode and the vehicle is stopped.
■Display
The display will return to the original display if the satellite switches are not oper-
ated for an extended period.
Even if the display is in satellite switch mode, it will switch in the event of a warning
or when the radar cruise control (if equipped) is used. If this occurs, press any of the
satellite switches or “DISP” switch on the steering wheel to return the display to sat-
ellite switch mode.