2014 Lexus IS250C Owner's Manual

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2-4. Using other driving systems
IS250C/350C_UExample of follow-up cruising
When following a vehicle driving slower than the set speed
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 any vehicles ahead driving slower than the
set speed
The system accelerates until the set speed is reached. The system then
returns to constant speed cruising.
Approach warning
When your vehicle is too close to a vehicle ahead, and sufficient auto-
matic deceleration via the cruise control is not possible, the display will
flash and the buzzer will sound to alert the driver. An example of this
would be if another driver cuts in front of you while you are following a
vehicle. Apply the brakes to ensure an appropriate vehicle-to-vehicle dis-
tance.
■ Warnings may not occur when
In the following instances, there is a possibility that the warnings will not
occur:
● When the speed of the vehicle ahead matches or exceeds your
vehicle speed
● When the vehicle ahead is traveling at an extremely slow speed
● Immediately after the cruise control speed was set
● At the instant the accelerator is applied

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Selecting conventional constant speed control mode
Constant speed control mode differs from vehicle-to-vehicle distance
control mode. When constant speed co ntrol mode is selected, your vehi-
cle will maintain a set speed regardless of whether or not there are other
vehicles in the lane ahead.
Press the “ON-OFF” button to
activate the cruise control.
Cruise control indicator will come
on.
Press the button again to deacti-
vate the cruise control.
Switch to constant speed con-
trol mode.
(Push the lever forward and
hold for approximately one sec-
ond.)
When in constant speed control
mode, to return to vehicle-to-vehi-
cle distance control mode, push
the lever forward again and hold
for approximately 1 second.
After the desired speed has been
set, it is not possible to return to
vehicle-to-vehicle distance control
mode.
If the “ENGINE START STOP”
switch is turned off and then turned
to IGNITION ON mode again, the
vehicle will automatically return to
vehicle-to-vehicle distance control
mode.

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Adjusting the speed setting:
→P. 1 9 6
Canceling and resuming the speed
setting: →P. 1 9 8
■Dynamic radar cruise control can be set when
●The shift lever is in the D or range 4 or higher of S has been selected.
●Range 4 or higher has been selected by using the paddle shift.
●Vehicle speed is above approximately 30 mph (50 km/h).
■Accelerating after setting the vehicle speed
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.
■Automatic cancelation of vehicle-to-vehicle distance control
Vehicle-to-vehicle distance control driving is automatically canceled in the follow-
ing situations:
●Actual vehicle speed falls below approximately 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 (when the wiper switch is set
to the “AUTO” mode or the high speed wiper operation position).
●When snow mode is set.
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.
■Automatic cancelation of constant speed control
The cruise control will stop maintaining the vehicle speed in the following situations:
●Actual vehicle speed is more than approximately 10 mph (16 km/h) below the
set vehicle speed.
At this time, the memorized set speed is not retained.
●Vehicle speed falls below approximately 25 mph (40 km/h).
●VSC is activated.

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■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.
■Warning lights, messages and buzzers for dynamic radar cruise control
Warning lights, messages and buzzers are used to indicate a system malfunction or
to inform the driver of the need for caution while driving. (→P. 500)
Grille cover
Radar sensor

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■CertificationFor vehicles sold in U.S.A.
FCC ID: HYQDNMWR005
This device complies with part 15 of the FCC Rules. Operation is subject to the fol-
lowing two conditions: (1) This device may not cause harmful interference, and (2)
this device must accept any interference received, including interference that may
cause undesired operation.
FCC WARNING
Changes or modifications not expressly approved by the party responsible for
compliance could void the user's authority to operate the equipment.
Radio frequency radiation exposure Information:
This equipment complies with FCC radiation exposure limits set forth for an uncon-
trolled environment.
This equipment should be installed and operated with minimum distance of 20 cm
between the radiator (antenna) and your body.
This transmitter must not be co-located or operating in conjunction with any other
antenna or transmitter. For vehicles sold in Canada
Operation is subject to the following two conditions: (1) this device may not cause
interference, and (2) this device must accept any interference, including interfer-
ence that may cause undesired operation of the device.
L’utilisation de ce dispositif est autorisée seulement aux deux conditions suivantes:
(1) il ne doit pas produire de brouillage, et (2) l’utilisateur du dispositif doit être prêt
à accepter tout brouillage radioélectrique reçu, même si ce brouillage est suscepti-
ble de compromettre le fonctionnement du dispositif.

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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 appropri-
ate, adjust the vehicle speed, as well as the distance between your vehicle and vehi-
cles 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.

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CAUTION
■To avoid inadvertent cruise control activation
Switch the cruise control off using the “ON-OFF” button when not in use.
■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 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
Vehicle speed may exceed the set speed when driving down a steep hill.
●At entrances to expressways
●When weather conditions are bad enough that they may prevent the sensors
from functioning correctly (fog, snow, sandstorm, heavy rain, etc.)
●When an approach warning buzzer is heard often
●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. 200) 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 sensor 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 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.
Otherwise, the system may not function correctly and could result in an accident.
●Keep the sensor and grille cover clean at all times.
Clean the sensor and 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 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 cover or surrounding
area.
●Do not modify or paint the sensor and grille cover.
●Do not replace them with non-genuine parts.