2014 Lexus IS250 Drive

2644-5. Using the driving support systems
IS250_EE(OM53C51E)
■Operation of the air conditioning system in Eco drive mode
Eco drive mode controls the heating/cooling operations and fan speed of the air condi-
tioning system to enhance fuel efficiency (→P. 376). To improve air conditioning perfor-
mance, adjust the fan speed or turn off Eco drive mode.
■Sport mode automatic deactivation
Sport mode is automatically deactivated if the engine switch is turned off after driving in
sport mode.

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.

2704-5. Using the driving support systems
IS250_EE(OM53C51E)
CAUTION
■The ABS does not operate effectively when
●The limits of tire gripping performance have been exceeded (such as excessively
worn tires on a snow covered road).
●The vehicle hydroplanes while driving at high speed on wet or slick roads.
■Stopping distance when the ABS is operating may exceed that of normal conditions
The ABS is not designed to shorten the vehicle’s stopping distance. Always maintain a
safe distance from the vehicle in front of you, especially in the following situations:
●When driving on dirt, gravel or snow-covered roads
●When driving with tire chains
●When driving over bumps in the road
●When driving over roads with potholes or uneven surfaces
■TRC may not operate effectively when
Directional control and power may not be achievable while driving on slippery road
surfaces, even if the TRC system is operating.
Drive the vehicle carefully in conditions where stability and power may be lost.
■Hill- start assist control does not operate effectively when
●Do not overly rely on hill-start assist control. Hill-start assist control may not operate
effectively on steep inclines and roads covered with ice.
●Unlike the parking brake, hill-start assist control is not intended to hold the vehicle
stationary for an extended period of time. Do not attempt to use hill-start assist con-
trol to hold the vehicle on an incline, as doing so may lead to an accident.
■When the VSC is activated
The slip indicator light flashes. Always drive carefully. Reckless driving may cause an
accident. Exercise particular care when the indicator light flashes.
■When the TRC/VSC systems are turned off
Be especially careful and drive at a speed appropriate to the road conditions. As these
are the systems to help ensure vehicle stability and driving force, do not turn the TRC/
VSC systems off unless necessary.
■Replacing tires
Make sure that all tires are of the specified size, brand, tread pattern and total load
capacity. In addition, make sure that the tires are inflated to the recommended tire infla-
tion pressure level.
The ABS, TRC and VSC systems will not function correctly if different tires are installed
on the vehicle.
Contact any authorized Lexus dealer or repairer, or another duly qualified and
equipped professional for further information when replacing tires or wheels.
■Handling of tires and the suspension
Using tires with any kind of problem or modifying the suspension will affect the driving
assist systems, and may cause a system to malfunction.

2714-5. Using the driving support systems
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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
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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.

2774-5. Using the driving support systems
4
Driving
IS250_EE(OM53C51E)
CAUTION
■Limitations of the pre-crash safety system
Do not overly rely on the pre-crash safety system. Always drive safely, taking care to
observe your surroundings and checking for any obstacles or other road hazards.
Failure to do so may cause an accident resulting in death or serious injury.
■Handling the radar sensor
Observe the following to ensure the pre-crash safety 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.
■Cautions regarding the assist contents of the system
By means of alarms and brake control, the pre-crash safety system is intended to assist
the driver in avoiding collisions through the process of LOOK-JUDGE-ACT. There are
limits to the degree of assistance the system can provide, so please keep in mind the
following important points.
●Assisting the driver in watching the road
The pre-crash safety system is only able to detect obstacles directly in front of the
vehicle, and only within a limited range. 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 con-
ditions. It is still necessary for the driver to pay close attention to the vehicle’s sur-
roundings.
●Assisting the driver in making correct judgment
When attempting to estimate the possibility of a collision, the only data available to
the pre-crash safety system is that from obstacles it has detected directly in front of
the vehicle. Therefore, it is absolutely necessary for the driver to remain vigilant and
to determine whether or not there is a possibility of collision in any given situation.
●Assisting the driver in taking action
The pre-crash safety system’s braking assist feature is designed to help reduce the
severity of a collision, and so only acts when the system has judged that a collision is
unavoidable. This system by itself is not capable of automatically avoiding a collision
or bringing the vehicle to a stop safely. For this reason, when encountering a danger-
ous situation the driver must take direct and immediate action in order to ensure the
safety of all involved.

2784-5. Using the driving support systems
IS250_EE(OM53C51E)
The Blind Spot Monitor is a system that has 2 functions;
●The Blind Spot Monitor function
Assists the driver in making the decision when changing lanes
●The Rear Crossing Traffic Alert function
Assists the driver when backing up
These functions use same sensors.
BSM (Blind Spot Monitor)∗
∗
: If equipped
Summary of the Blind Spot Monitor
BSM main switch
Pressing the switch turns the system on or off. When the switch is set to on, the
switch’s indicator illuminates and the buzzer sounds. Common switch for Blind Spot
Monitor function and Rear Crossing Traffic Alert function.
Outside rear view mirror indicators
Blind Spot Monitor function:
When a vehicle is detected in the blind spot, the outside rear view mirror indicator
comes on while the turn signal lever is not operated and the outside rear view mirror
indicator flashes while the turn signal lever is operated.
Rear Crossing Traffic Alert function:
When a vehicle approaching from the right or left rear of the vehicle is detected, the
outside rear view mirror indicators flash.
Rear Crossing Traffic Alert buzzer
When a vehicle approaching from the right or left rear of the vehicle is detected, a
buzzer sounds from behind the rear seat.
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2834-5. Using the driving support systems
4
Driving
IS250_EE(OM53C51E)
The Blind Spot Monitor function uses radar sensors to detect vehicles that are
traveling in an adjacent lane in the area that is not reflected in the outside rear
view mirror (the blind spot), and advises the driver of the vehicles existence via
the outside rear view mirror indicator.
The areas that vehicles can be detected in are outlined below.
The range of the detection area
extends to:
Approximately 3.5 m (11.5 ft.) from
the side of the vehicle
The first 0.5 m (1.6 ft.) from the side of
the vehicle is not in the detection area
Approximately 3 m (9.8 ft.) from the
rear bumper
Approximately 1 m (3.3 ft.) forward
of the rear bumper
The Blind Spot Monitor function
The Blind Spot Monitor function detection areas
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CAUTION
■Cautions regarding the use of the system
The driver is solely responsible for safe driving. Always drive safely, taking care to
observe your surroundings.
The Blind Spot Monitor function is a supplementary function which alerts the driver
that a vehicle is present in the blind spot. Do not overly rely on the Blind Spot Monitor
function. The function cannot judge if it is safe to change lanes, therefore over reliance
could cause an accident resulting in death or serious injury.
According to conditions, the system may not function correctly. Therefore the driver’s
own visual confirmation of safety is necessary.