2010 Lexus IS250 brake

166
2-3. Operating the lights and windshield wipers
AFS (vehicles with discharge headlights)
AFS (Adaptive Front-lighting System) improves visibility at intersections
and on curves by automatically adjusting the level of the headlights
according to vehicle speed and the degree of the tire’s angle as con-
trolled by steering input.
Operates at speeds of 6 mph (10 km/h) or higher.
■Deactivating AFS
How to switch: P. 3 4 2
“AFS OFF” turns on when the AFS is deactivated.
■Daytime running light system
To make your vehicle more visible to other drivers, the headlights turn on automati-
cally (at a reduced intensity) whenever the engine is started and the parking brake
is released. Daytime running lights are not designed for use at night.
■Headlight control sensor
The sensor may not function properly if an
object is placed on the sensor, or anything
that blocks the sensor is affixed to the wind-
shield.
Doing so interferes with the sensor detecting
the level of ambient light and may cause the
automatic headlight system to malfunction.

176
2-4. Using other driving systems
■Adjusting the speed setting
Increase speed
Decrease speed
Hold the lever until the desired
speed setting is obtained.
Fine adjustment of the set
speed (approximately 1.0 mph
[1.6 km/h]) can be made by
lightly pressing the lever up or
down and releasing it.
■Canceling and resuming regular acceleration
Cancel
Push the lever towards you to
cancel cruise control.
The speed setting is also can-
celed when the brakes are
applied or the clutch (manual
transmission) is depressed.
Resume
To resume cruise control and
return to the set speed, push the
lever up.

182
2-4. Using other driving systems
■Changing the vehicle-to-vehicle distance
Pressing the button changes the
vehicle-to-vehicle distance as
follows:
Long
Medium
Short
The vehicle-to-vehicle distance
is set automatically to long
mode when the “ENGINE
START STOP” switch is turned
to IGNITION ON mode.
If a vehicle is running ahead of
you, the preceding vehicle mark
will also be displayed.
■Canceling and resuming the speed control
Pulling the lever toward you
cancels the cruise control.
The speed setting is also can-
celed when the brakes are
applied.
Pushing the lever up resumes
the cruise control and returns
vehicle speed to the set
speed.
Resuming is available when the
vehicle speed is more than
approximately 25 mph (40 km/
h).
Preceding
vehicle mark

183
2-4. Using other driving systems
2
When driving
Driving in vehicle-to-vehicle distance control mode
This mode employs a sensor to detect the presence of vehicles up to
approximately 400 ft. (120 m) ahead and to judge the distance between
your vehicle and those the vehicle ahead of you.
Note that vehicle-to-vehicle distance will close when traveling on long down-
hill slopes.
Example of constant speed cruising
When there are no vehicles ahead
The vehicle travels at the speed set by the driver. The desired vehicle-to-vehi-
cle distance can also be set by operating the vehicle-to-vehicle distance con-
trol.
Example of deceleration cruising
When the vehicle ahead is driving slower than the set speed
When a vehicle is detected running ahead of you, the system automatically
decelerates your vehicle. When a greater reduction in vehicle speed is nec-
essary, the system applies the brakes. A warning tone warns you when the
system cannot decelerate sufficiently to prevent your vehicle from closing in
on the vehicle ahead.

184
2-4. Using other driving systems
Example 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.

189
2-4. Using other driving systems
2
When driving
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 autoris
ée 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 susceptible de compromettre le fonctionnement du dispositif.
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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2-4. Using other driving systems
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 and 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
●When your vehicle is towing a trailer or during emergency towing
■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
approach warning (P. 480) 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

191
2-4. Using other driving systems
2
When driving
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:
●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 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.