2014 Lexus IS250 brakes

2344-5. Using the driving support systems
IS250_EE(OM53C51E)
When your vehicle is too close to a vehicle ahead, and sufficient automatic
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 distance.
■Wa r n i n g s m a y n o t o c c u r w h e n
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
When constant speed control mode is selected, your vehicle will maintain a set
speed without controlling the vehicle-to-vehicle distance. Select this mode only
when vehicle-to-vehicle distance control mode does not function correctly due
to dirt etc.
Press the “ON/OFF” button to acti-
vate the cruise control.
Press the button again to deactivate the
cruise control.
Switch to constant speed control
mode.
(Push the lever forward and hold for
approximately 1 second.)
Constant speed control mode indicator will come on.
When in constant speed control mode, to return to vehicle-to-vehicle distance con-
trol 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 switch is turned off and then turned to IGNITION ON mode again, the
vehicle will automatically return to vehicle-to-vehicle distance control mode.
Adjusting the speed setting: →P. 2 2 6
Canceling and resuming the speed setting: →P. 2 2 6
Approach warning
Selecting conventional constant speed control mode
1
2

2394-5. Using the driving support systems
4
Driving
IS250_EE(OM53C51E)
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 distance
between the driver’s own vehicle and a designated vehicle traveling ahead is appro-
priate 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.
■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 result-
ing 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
●When your vehicle is towing a trailer or during emergency towing

2404-5. Using the driving support systems
IS250_EE(OM53C51E)
CAUTION
■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. 234) 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
■Conditions under which the vehicle-to-vehicle distance control may not function cor-
rectly
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 a 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 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 sen-
sor 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 surrounding area.
●Do not modify or paint the sensor and grille cover.
●Do not replace them with non-genuine parts.

2524-5. Using the driving support systems
IS250_EE(OM53C51E)
■Sensor detection information
●The sensor’s detection areas are limited to the areas around the vehicle’s front corner
and rear bumpers.
●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. (Wiping the sensors will resolve this prob-
lem.)
• The sensor is frozen. (Thawing the area will resolve this problem.)
In especially cold weather, if a sensor is frozen the screen may show an abnormal
display, or obstacles may not be detected.
• 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.
• The area directly under the bumpers is not detected.
• If obstacles draw too close to the sensor.
• A non-genuine Lexus suspension (lowered suspension etc.) is installed.
• People may not be detected if they are wearing certain types of clothing.
In addition to the examples above, there are instances in which, because of their shape,
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 sound waves
• Sharply-angled objects
• Low obstacles
• Tall obstacles with upper sections projecting outwards in the direction of your vehi-
cle
●The following situations may occur during use.
• Depending on the shape of the obstacle and other factors, the detection distance
may shorten, or detection may be impossible.
• Obstacles may not be detected if they are too close to the sensor.
• There will be a short delay between obstacle detection and display. Even at slow
speeds, there is a possibility that the obstacle will come within the sensor’s detection
areas before the display is shown and the warning beep sounds.
• Thin posts or objects lower than the sensor may not be detected when approached,
even if they have been detected once.
• It might be difficult to hear beeps due to the volume of the audio system or air flow
noise of the air conditioning system.
■If a message is displayed on the multi-information display
→P. 4 8 4

2654-5. Using the driving support systems
4
Driving
IS250_EE(OM53C51E)
◆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
◆VSC+ (Vehicle Stability Control+)
Provides cooperative control of the ABS, TRC, VSC and EPS.
Helps to maintain directional stability when swerving on slippery road sur-
faces by controlling steering performance.
◆TRC (Traction Control)
Helps to maintain drive power and prevent the drive wheels from spinning
when starting the vehicle or accelerating on slippery roads
◆Hill-start assist control
Prevents the vehicle from rolling backward when starting on an incline or slip-
pery slope
◆EPS (Electric Power Steering)
Employs an electric motor to reduce the amount of effort needed to turn the
steering wheel
Driving assist systems
To help enhance driving safety and performance, the following systems oper-
ate 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.

2664-5. Using the driving support systems
IS250_EE(OM53C51E)
◆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 surfaces by
controlling the brakes, engine output
◆PCS (Pre-Crash Safety system) (if equipped)
→P. 2 7 1
◆Emergency brake signal
When the brakes are applied suddenly, the stop lights automatically flash to
alert the vehicle behind
◆BSM (Blind Spot Monitor) (if equipped)
→P. 2 7 8
The slip indicator light will flash while
the TRC/VSC systems are operating.
When the TRC/VSC systems are operating

2714-5. Using the driving support systems
4
Driving
IS250_EE(OM53C51E)
◆Pre-crash warning
When a high possibility of a frontal
collision is detected, the pre-crash
safety system warning light flashes, a
buzzer sounds and a message is
shown on the multi-information dis-
play to urge the driver to take eva-
sive action.
◆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.
The system may not warn the driver using a warning light, warning display and
buzzer when the system detects and judges braking operations.
◆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 deter-
mines that a collision is unavoidable, the brakes are automatically applied to
reduce the collision speed.
PCS (Pre-Crash Safety system)∗
∗
: If equipped
When the radar sensor detects the possibility of a frontal collision, brakes are
automatically engaged to lessen impact as well as vehicle damage.
The pre-crash safety system can be turned on and off as necessary by operat-
ing the switch. (→P. 2 7 2 )

2734-5. Using the driving support systems
4
Driving
IS250_EE(OM53C51E)
■The pre-crash safety system is operational when
The PCS OFF switch is not pressed and the following conditions are met:
●Pre-crash warning:
• Vehicle speed is greater than about 15 km/h (10 mph).
• The speed at which your vehicle is approaching the obstacle or the vehicle running
ahead of you is greater than about 15 km/h (10 mph).
●Pre-crash brake assist:
• The VSC OFF switch is not pressed.
• Vehicle speed is greater than about 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 about 30 km/h (19 mph).
• The brake pedal is depressed.
●Pre-crash braking:
• The VSC OFF switch is not pressed.
• Vehicle speed is greater than about 15 km/h (10 mph).
• The speed at which your vehicle is approaching the obstacle or the vehicle running
ahead of you is greater than about 15 km/h (10 mph).
■Conditions that may trigger the system even if there is no danger of a collision
●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 left-turn (left-hand drive vehicles) or right-turn
(right-hand drive vehicles)
●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
●When there is a metal plate in the road in front of the vehicle on a downhill slope
●When climbing a steep hill causes an overhead billboard or other metallic structure to
appear directly in the vehicle’s line of travel
●When driving under an overpass
●When an extreme change in vehicle height occurs
●When passing through certain toll gates
●When passing through a tunnel
●When the radar sensor moves off position due to its surrounding area being subjected
to a strong impact
When the system is activated in the situations described above, there is also a possibility
that the brakes will be applied with a force greater than normal.